题解

114 条题解

  • 4
    @ 2017-07-04 17:38:31

    Rssqzqyp 2017.7.4

    算法最小生成树,算是模版题,不加优化58毫秒
    加优化25s左右

    #include<bits/stdc++.h>
    using namespace std;
    const int maxn=1000100;
    int n,m;
    int fa[maxn];
    struct note
    {
        int s,v,w;
    }e[maxn];
    bool cmp(note a,note b)
    {
        return a.w<b.w;
    }
    int ff(int x)
    {
        return fa[x]=(fa[x]==x)?x:ff(fa[x]);
    }
    int main()
    {
        cin>>n>>m;
        for(int i=1;i<=m;i++)
        cin>>e[i].s>>e[i].v>>e[i].w;
        sort(e+1,e+m+1,cmp);
        int rest=n-1;
        int ans1=0,ans2=0;
        for(int i=1;i<=m;i++)
        fa[i]=i;
        for(int i=1;i<=m;i++)
        {
            if(!rest) break; 
            int p1,p2;
            p1=ff(e[i].s);
            p2=ff(e[i].v);
            if(p1==p2) continue;
            fa[p1]=p2;
            ans1++;
            rest--;
            ans2=e[i].w;
        }
    cout<<ans1<<" "<<ans2;
    return 0;
    }
    
  • 1
    @ 2019-02-13 11:06:31

    #include<cmath>
    #include<cstdio>
    #include<cstring>
    #include<iostream>
    #include<algorithm>
    #include<queue>
    #include<stdio.h>
    #include<string.h>
    #define Max 1000100
    using namespace std;
    int fa[Max];
    int find(int x)
    {
    if(fa[x]==x)
    return x;
    return fa[x]=find(fa[x]);
    }
    struct road
    {
    int u,v,c;
    }f[Max];
    bool cmp(road a,road b)
    {
    return a.c<b.c;
    }
    int main()
    {
    int n,m;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++)
    {
    scanf("%d%d%d",&f[i].u,&f[i].v,&f[i].c);
    }
    sort(f+1,f+1+m,cmp);
    for(int i=1;i<=m;i++)
    {
    fa[i]=i;
    }
    int ans1,ans2;
    ans1=0,ans2=0;
    int rest;
    rest=n-1;
    for(int i=1;i<=m;i++)
    {
    if(!rest)
    break;
    int x,y;
    x=find(f[i].u);
    y=find(f[i].v);
    if(x==y)
    continue;
    fa[x]=y;
    ans1++;
    rest--;
    ans2=f[i].c;
    }
    cout<<ans1<<" "<<ans2<<endl;
    return 0;
    }

  • 1
    @ 2017-07-04 17:41:09

    最小生成树裸题

    #include<bits/stdc++.h>
    using namespace std;
    const int maxn=1000010;
    struct Edge
    {
        int u,v,c;
    }e[maxn];
    int n,gary,m,p[maxn],ans;
    inline int read()
    {
        int f=1,x=0;char ch=getchar();
        while(ch<'0'||ch>'9'){if(ch=='-') f=-1;ch=getchar();}
        while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
        return x*f;
    }
    bool cmp(Edge a,Edge b)
    {
        return a.c<b.c;
    }
    void init()
    {   
        n=read();m=read();gary=n-1;
        for(int i=1;i<=m;i++)
        {
            e[i].u=read();
            e[i].v=read();
            e[i].c=read();
        }
    }
    int find(int x)
    {
        if(x!=p[x]) p[x]=find(p[x]);
        return p[x];
    }
    void work()
    {
        sort(e+1,e+m+1,cmp);
        for(int i=1;i<=n;i++)
        p[i]=i;
        for(int i=1;i<=m;i++)
        {
            if(!gary) break;
            int x=find(e[i].u),y=find(e[i].v);
            if(x!=y)
            {
                gary--;
                p[x]=y;
                ans=max(e[i].c,ans);
            }
        }
        cout<<n-1<<" "<<ans<<endl;
    }
    int main()
    {
        init();
        work();
    }
    
  • 0
    @ 2018-05-08 19:53:38

    Accepted

    状态 耗时 内存占用

    #1 Accepted 8ms 336.0 KiB
    #2 Accepted 2ms 360.0 KiB
    #3 Accepted 3ms 384.0 KiB
    #4 Accepted 2ms 384.0 KiB
    #5 Accepted 2ms 372.0 KiB
    #6 Accepted 4ms 256.0 KiB
    #7 Accepted 4ms 360.0 KiB
    #8 Accepted 6ms 384.0 KiB
    #9 Accepted 7ms 480.0 KiB
    #10 Accepted 7ms 512.0 KiB
    ---------------------------------------------------
    着毫秒数乱七八糟的,强迫症犯了

  • 0
    @ 2018-03-08 18:23:12

    #include<cstdio>
    #include<algorithm>
    #include<cmath>
    #include<cstring>
    #include<cstdlib>
    #include<iostream>
    #define ll long long
    using namespace std;

    struct node
    {
    int l;
    int r;
    int val;
    }a[10005];

    int f[10005];
    int n , m ,ans,maxn;

    int cmp(node x,node y)
    {
    return x.val < y.val;
    }

    int find(int x)
    {
    if(f[x]==x)
    {
    return x;
    }
    return f[x]=find(f[x]);
    }

    int Kruskal()
    {
    for(int i = 1;i <= m;i++)
    {
    int u = a[i].l;
    int v = a[i].r;
    int uu = find(u);
    int vv = find(v);
    if(uu == vv)
    {
    continue;
    }else
    {
    f[vv] = uu;/*f[uu] = vv;*/
    ans++;
    maxn = max(maxn,a[i].val);
    }
    }
    }

    int main()
    {
    cin >> n >> m;
    for(int i = 1;i <= m;i++)
    {
    cin >> a[i].l >> a[i].r >> a[i].val;
    }
    for(int i = 1;i <= n;i++)
    {
    f[i] = i;
    }
    sort(a+1,a+1+m,cmp);
    Kruskal();
    cout << ans << " " << maxn <<endl;
    return 0 ;
    }

  • 0
    @ 2017-11-19 11:53:53

    #include <iostream>
    #include <cstdio>
    #include <vector>
    #include <algorithm>
    using namespace std;
    const int N = 1e4 + 7;
    const int M = 1e3 + 7;
    int n, m, cnt, ans, f[M];

    template <class T>
    inline void read(T &x){
    x = 0;
    static char buf = getchar();
    for ( ;!isdigit(buf); buf = getchar());
    for ( ;isdigit(buf); buf = getchar())
    x = x * 10 + buf - 48;
    }

    struct edge{
    int u, v, w;
    }way[N];

    bool cmp(const edge &x, const edge &y){
    return x.w < y.w;
    }

    inline void init(){
    for (int i = 1; i <= n; i ++)
    f[i] = i;
    }

    int find(int x){
    return x == f[x] ? x : f[x] = find(f[x]);
    }

    void kruskal(){
    init();
    sort(way + 1, way + m + 1, cmp);
    for (int i = 1; i <= m; i ++){
    int fu = find(way[i].u), fv = find(way[i].v);
    if (fu != fv) cnt ++, f[fv] = fu;
    if (cnt == n - 1) {
    ans = way[i].w; break ;
    }
    }
    }

    void work(){
    read(n), read(m);
    for (int i = 1; i <= m; i ++)
    read(way[i].u), read(way[i].v), read(way[i].w);
    kruskal();
    cout << cnt << ' ' << ans << endl;
    }

    int main(){
    work(); return 0;
    }

  • 0
    @ 2017-10-18 20:17:34

    没有人发prim的话我来补一个。。给学最小生成树的oier提供个模板。

    #include<iostream>
    #include<cstdio>
    using namespace std;
    int dis[305][305],mina[305],u[305],n,m,i,x,y,be,j,k,ans,minx,minn,tot;
    int main()
    {
        cin>>n>>m;
        minn=0x7fffffff/3;
        for(i=0;i<=n;i++)
        {
            mina[i]=0x7fffffff/3;
            for(j=0;j<=n;j++)
            {
                dis[i][j]=0x7fffffff/3;
            }
        }
        for(i=1;i<=m;i++)
        {
            cin>>x>>y;
            cin>>dis[y][x];
            dis[x][y]=dis[y][x];
            if(dis[x][y]<minn)
            {
                minn=dis[x][y];
                be=x;
            }
        }
        mina[x]=0;
        for(int l=1;l<=n;l++)
        {
            k=0;
        for(i=1;i<=n;i++)
        {
            if(mina[k]>mina[i] && !u[i])
            {
                k=i;
            }
        }
            u[k]=1;
            for(j=1;j<=n;j++)
            {
                if(!u[j] && mina[j]>dis[j][k])
                {
                    mina[j]=dis[j][k];
                }
            }
        }
          for(int q=1;q<=n;q++)
            ans=max(mina[q],ans); 
            cout<<n-1<<" "<<ans;
        return 0;
    }
    
  • 0
    @ 2017-05-29 12:45:00
    #include <cmath>
    #include <cstdio>
    #include <cstring>
    #include <algorithm>
    #include <vector>
    using namespace std;
    
    const int oo_min=0xcfcfcfcf,oo_max=0x3f3f3f3f;
    
    struct edge_1
    {
        int x,y,d;
    };
    
    int n,m,cnt,max_d;
    vector<int> fa;
    vector<edge_1> e;
    
    bool cmp_edge_1(edge_1 x,edge_1 y)
    {
        return x.d<y.d;
    }
    
    int find_fa_1(int x)
    {
        return ((fa[x]==x)?x:(fa[x]=find_fa_1(fa[x])));
    }
    
    int unite_1(int x,int y)
    {
        if (fa[(fa[y]=find_fa_1(fa[y]))]!=(fa[x]=find_fa_1(fa[x])))
        {
            fa[fa[y]]=fa[x];
            return 1;
        }
        else
            return 0;
    }
    
    int main()
    {
        while (~scanf("%d%d",&n,&m))
        {
            fa.resize(n+1);
            for (int i=1;i<=n;i++)
                fa[i]=i;
            e.resize(m+1);
            for (int i=1;i<=m;i++)
            {
                int x,y,d;
                scanf("%d%d%d",&x,&y,&d);
                e[i].x=x,e[i].y=y,e[i].d=d;
            }
            sort(e.begin()+1,e.end(),cmp_edge_1);
            cnt=max_d=0;
            for (int i=1;i<=m&&cnt<n-1;i++)
            {
                int suc=unite_1(e[i].x,e[i].y);
                cnt+=suc;
                max_d=max(max_d,e[i].d*suc);
            }
            printf("%d %d\n",cnt,max_d);
        }
    }
    
  • 0
    @ 2017-04-08 13:29:25
    #include <bits/stdc++.h>
    using namespace std;
    int f[305];
    struct edge
    {
        int from,to,len;
    }road[10005];
    bool comp(edge a,edge b){
        return a.len<b.len;
    }
    int getf(int x)
    {
        return f[x]==x?x:f[x]=getf(f[x]);
    }
    int main()
    {
        int n,m,maxw=0;
        scanf("%d%d",&n,&m);
        for(int i=1;i<=m;i++)
            scanf("%d%d%d",&road[i].from,&road[i].to,&road[i].len);
        std::sort(road+1,road+m+1,comp);
        for(int i=1;i<=n;i++) f[i]=i;
        for(int i=1,j=0;i<=m && j<n-1;i++) {
            int p1=getf(road[i].from);
            int p2=getf(road[i].to);
            if(p1!=p2) {
                maxw=road[i].len;
                f[p1]=p2;
            }
        }
        printf("%d %d",n-1,maxw);
        return 0;
    }
    
  • 0
    @ 2016-03-20 11:50:46

    记录信息
    评测状态 Accepted
    题目 P1190 繁忙的都市
    递交时间 2016-03-20 11:49:59
    代码语言 C++
    评测机 VijosEx
    消耗时间 0 ms
    消耗内存 368 KiB
    评测时间 2016-03-20 11:50:01
    评测结果
    编译成功

    测试数据 #0: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #1: Accepted, time = 0 ms, mem = 364 KiB, score = 10
    测试数据 #2: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #3: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #4: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #5: Accepted, time = 0 ms, mem = 364 KiB, score = 10
    测试数据 #6: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #7: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #8: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    测试数据 #9: Accepted, time = 0 ms, mem = 368 KiB, score = 10
    Accepted, time = 0 ms, mem = 368 KiB, score = 100
    代码
    #include<cstdio>
    #include<algorithm>
    using namespace std;

    const int MaxN = 300 + 10, MaxM = 10000 + 10;

    int N, M, A, B, Max;

    struct Node {
    bool root;
    int parent;
    }node[MaxN];

    struct Eage {
    int To, From, Cost;
    bool operator < (const Eage& Element) const {
    return Element.Cost > Cost;
    }
    }E[MaxM];

    int getInt() {
    int Return = 0;
    char Get = getchar();
    while(Get >= '0' && Get <= '9') {
    Return = Return * 10 + (Get - '0');
    Get = getchar();
    }
    return Return;
    }

    int Find(int Element) {
    int theRoot = Element;
    while (!node[theRoot].root)theRoot = node[theRoot].parent;
    int parentNode;
    int Now = Element;
    while (Now != theRoot) {
    parentNode = node[Now].parent; node[Now].parent = theRoot; Now = parentNode;
    }
    return theRoot;
    }

    void Unite(int rootA, int rootB)
    {
    if (node[rootA].parent < node[rootB].parent) {
    node[rootB].parent += node[rootA].parent;
    node[rootA].root = 0;
    node[rootA].parent = rootB;
    }
    else {
    node[rootA].parent += node[rootB].parent;
    node[rootB].root = 0;
    node[rootB].parent = rootA;
    }
    }

    int main() {
    N = getInt(); M = getInt();
    for(int i = 1; i <= N; ++i) {
    node[i].root = 1;
    node[i].parent = i;
    }
    for(int i = 1; i <= M; ++i) {
    E[i].From = getInt();
    E[i].To = getInt();;
    E[i].Cost = getInt();
    }
    sort(E + 1, E + M + 1);
    for(int i = 1, j = N; j > 1; ++i) {
    A = Find(E[i].From); B = Find(E[i].To);
    if(A != B) {
    Unite(A, B);
    Max = max(Max, E[i].Cost); --j;
    }
    }
    printf("%d %d", N - 1, Max);
    return 0;
    }

  • 0
    @ 2016-01-22 09:15:42

    此题似乎并不需要生成树,二分答案即可。
    时间复杂度为O(nlogn)

    #include <cstdio>
    #include <vector>
    #include <algorithm>
    
    using namespace std;
    
    #define NMAX 300
    
    struct Edge {
        Edge() : u(0), v(0), w(0) {}
        Edge(int _u, int _v, int _w) : u(_u), v(_v), w(_w) {}
    
        int u;
        int v;
        int w;
    };  // struct Edge
    
    typedef vector<Edge *>::iterator iterator_t;
    
    static int n;
    static int m;
    static int size;
    static int set[NMAX + 10];
    static vector<Edge *> edges;
    static int answer;
    
    bool compare(const Edge *a, const Edge *b) {
        return a->w < b->w;
    }
    
    inline void make_set() {
        size = n;
    
        for (int i = 1; i <= n; i++) {
            set[i] = i;
        }  // for
    }
    
    inline int find_set(int x) {
        return x == set[x] ? x : set[x] = find_set(set[x]);
    }
    
    inline void union_set(int x, int y) {
        x = find_set(x);
        y = find_set(y);
    
        if (x != y) {
            set[x] = y;
            size--;
        }
    }
    
    void initialize() {
        scanf("%d %d", &n, &m);
    
        edges.reserve(m);
        int x, y, c;
        for (int i = 0; i < m; i++) {
            scanf("%d %d %d", &x, &y, &c);
    
            if (x == y)
                continue;
    
            Edge *p = new Edge(x, y, c);
            edges.push_back(p);
        }  // for
    
        sort(edges.begin(), edges.end(), compare);
    }
    
    void quit() {
        printf("%d %d", n - 1, answer);
    }
    
    bool test(int limit) {
        make_set();
    
        for (iterator_t beg = edges.begin();
             beg != edges.end() and (*beg)->w <= limit;
             beg++) {
            Edge *e = *beg;
            union_set(e->u, e->v);
        }  // for
    
        return size == 1;
    }
    
    int main() {
        initialize();
    
        int left = 0, right = edges.size() - 1;
        while (right - left > 1) {
            int mid = (left + right) >> 1;
    
            bool flag = test(edges[mid]->w);
            if (flag) {
                right = mid;
            } else {
                left = mid;
            }
        }  // while
    
        if (left != right and !test(edges[left]->w)) {
            left = right;
        }
    
        answer = edges[left]->w;
    
        quit();
        return 0;
    }  // function main
    
    
    • @ 2016-11-09 22:58:16

      最小生成树的代码长度仅为您这个的1/4啊

    • @ 2017-05-04 13:04:40

      是啊

  • 0
    @ 2015-10-07 10:39:08
  • 0
    @ 2015-10-07 10:25:35

    大神们,这一道题能用prim做么?在线等

  • 0
    @ 2015-08-29 11:27:44

    半裸的Krustal
    #include <cstdio>
    #include <cstring>
    #include <algorithm>

    const int maxn=305;
    const int maxm=maxn*maxn/2;
    int p[maxn];

    struct edge
    {
    int from,to;
    int weight;
    }road[maxm];

    bool operator < (const edge& A,const edge& B)
    {
    return A.weight < B.weight;
    }
    int getP(int x)
    {
    return p[x]==x?x:p[x]=getP(p[x]);
    }
    int main()
    {
    int N,M;
    scanf("%d%d",&N,&M);
    for(int i=0;i<M;i++) {
    scanf("%d%d%d",&road[i].from,&road[i].to,&road[i].weight);
    }
    std::sort(road,road+M);

    int maxW=0;
    for(int i=1;i<=N;i++) p[i]=i;
    for(int i=0,j=N;j>1;i++) {
    int p1=getP(road[i].from);
    int p2=getP(road[i].to);
    if(p1!=p2) {
    maxW=road[i].weight;
    p[p1]=p2;
    j--;
    }
    }

    printf("%d %d",N-1,maxW);
    return 0;
    }

  • 0
    @ 2015-08-19 16:34:33

    该题显然用n-1条边将每个节点连接。
    要求最大权值最小,说明构造的最小生成树最大的边权输出即可。
    因为 最小生成树以贪心的方法构造,其中选的边都是可用的中最小的,假如换掉其中一条边,必然使总权值变大,且最大边权要么仍等于最小生成树的最大边权,要么比其大。 因为 若换的为最小生成树中不是最大边权的边,那么最大边权保持不变,否则使得最大边权变大。
    由此可以得出最大边权最小必然是最小生成树的最大边权。

    由此得出算法 Kruscal算法即可。

    ###代码如下

    program p1190;
    type rec=record
    s,e,v:longint;
    end;
    var n,m:longint;
    ans,i,j,k:longint;
    father:array[1..300] of integer;
    map:array[1..90000] of rec;

    function max(a,b:longint):longint;
    begin
    if a>b then exit(a);
    exit(b);
    end;

    procedure qsort(i,j:longint);
    var l,r,mid:longint;
    temp:rec;
    begin
    l:=i;
    r:=j;
    mid:=map[(l+r)>>1].v;
    while l<=r do
    begin
    while map[l].v<mid do inc(l);
    while map[r].v>mid do dec(r);
    if l<=r
    then
    begin
    temp:=map[l];
    map[l]:=map[r];
    map[r]:=temp;
    inc(l);
    dec(r);
    end;
    end;
    if l<j then qsort(l,j);
    if i<r then qsort(i,r);
    end;

    function find(x:longint):longint;
    begin
    if father[x]=x then exit(x);
    father[x]:=find(father[x]);
    exit(father[x]);
    end;

    procedure unite(a,b:longint);
    begin
    father[find(father[a])]:=find(father[b]);
    end;
    begin
    readln(n,m);
    for i:=1 to m do
    begin
    readln(map[i].s,map[i].e,map[i].v);
    map[i+m].s:=map[i].e;
    map[i+m].e:=map[i].s;
    map[i+m].v:=map[i].v;
    end;
    qsort(1,2*m);
    for i:=1 to n do father[i]:=i;
    for i:=1 to 2*m do
    begin
    if find(map[i].s)<>find(map[i].e)
    then
    begin
    unite(map[i].s,map[i].e);
    ans:=max(ans,map[i].v);
    end;
    end;
    write(n-1,' ',ans);
    end.
    ###评测结果

    测试数据 #0: Accepted, time = 23 ms, mem = 1840 KiB, score = 10
    测试数据 #1: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #2: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #3: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #4: Accepted, time = 15 ms, mem = 1844 KiB, score = 10
    测试数据 #5: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #6: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #7: Accepted, time = 15 ms, mem = 1844 KiB, score = 10
    测试数据 #8: Accepted, time = 0 ms, mem = 1840 KiB, score = 10
    测试数据 #9: Accepted, time = 46 ms, mem = 1840 KiB, score = 10
    Accepted, time = 99 ms, mem = 1844 KiB, score = 100

  • 0
    @ 2015-03-21 08:47:51

    #include<cstdio>
    #include<algorithm>

    using namespace std;

    struct kruskal{
    int a,b,value;
    };

    int n,m,son[1001],father[1001],total=0;
    kruskal edge[10000];

    bool cmp(const kruskal & a,const kruskal & b){
    return a.value<b.value;
    }

    int find(int x){
    return x==father[x] ? x : find(father[x]);
    }

    bool join(int x,int y){
    x=find(x);
    y=find(y);
    if(x==y){
    return false;
    }
    else if(son[x]<=son[y]){
    father[x]=y;
    son[y]+=son[x];
    }
    else{
    father[y]=x;
    son[x]+=son[y];
    }
    return true;
    }

    int main(){
    scanf("%d%d",&n,&m);
    for(int j=0;j<k;j++){
    sum=0;
    total=0;
    for(int i=1;i<=n;i++){
    father[i]=i;
    son[i]=1;
    }

    for(int i=0;i<m;i++){
    scanf("%d%d%d",&edge[i].a,&edge[i].b,&edge[i].value);
    }

    sort(edge,edge+m,cmp);

    for(int i=0;i<m;i++){
    if(join(edge[i].a,edge[i].b)){
    total++;
    sum+=edge[i].value;
    }
    if(total==n-1){
    printf("%d %d",total edge[i].value);
    return 0;
    }
    }
    }

  • 0
    @ 2014-10-29 16:22:51

    优先队列优化的Kruskal+并查集
    #include<iostream>
    #include<cstdio>
    #include<cstring>
    #include<string>
    #include<vector>
    #include<stack>
    #include<queue>
    #include<map>
    #include<set>
    #include<cmath>
    #include<algorithm>
    using namespace std;
    struct Edge
    {
    int u, v, dis;
    bool operator< (const Edge &rhs) const
    {
    return dis > rhs.dis;
    }
    };
    int n, m, maxs = 0;
    priority_queue<Edge> e;
    int fa[311];
    int FIND(int x)
    {
    if(fa[x] == x)return x;
    else return fa[x] = FIND(fa[x]);
    }
    int main()
    {
    //freopen("test.in","r",stdin);
    //freopen("test.out","w",stdout);
    ios::sync_with_stdio(false);
    cin >> n >> m;
    int tu, tv, tdis;
    for(int i = 0; i < m; ++i)
    {
    cin >> tu >> tv >> tdis;
    e.push((Edge){tu, tv, tdis});
    }
    memset(fa, 0, sizeof(fa));
    for(int i = 1; i <= n; ++i)fa[i] = i;
    while(!e.empty())
    {
    Edge cur = e.top();
    e.pop();
    int a = FIND(cur.u), b = FIND(cur.v);
    if(a == b)continue;
    fa[a] = b;
    maxs = cur.dis;
    }
    cout << n - 1 << " " << maxs << endl;
    return 0;
    }

    • @ 2014-10-29 16:25:29

      不过貌似因为用了STL所以速度很差……是不是我有哪里写错了- -|||
      测试数据 #0: Accepted, time = 93 ms, mem = 468 KiB, score = 10
      测试数据 #1: Accepted, time = 0 ms, mem = 284 KiB, score = 10
      测试数据 #2: Accepted, time = 0 ms, mem = 284 KiB, score = 10
      测试数据 #3: Accepted, time = 7 ms, mem = 284 KiB, score = 10
      测试数据 #4: Accepted, time = 0 ms, mem = 284 KiB, score = 10
      测试数据 #5: Accepted, time = 46 ms, mem = 368 KiB, score = 10
      测试数据 #6: Accepted, time = 31 ms, mem = 372 KiB, score = 10
      测试数据 #7: Accepted, time = 46 ms, mem = 368 KiB, score = 10
      测试数据 #8: Accepted, time = 62 ms, mem = 468 KiB, score = 10
      测试数据 #9: Accepted, time = 78 ms, mem = 472 KiB, score = 10

  • 0
    @ 2014-10-05 15:33:31

    program p1190;
    var
    sum,max,i,j,min,x,y,z,n,m,k:longint;
    a:array[1..1000,1..1000]of longint;
    b,c,d:array[1..1000]of longint;
    procedure prim;
    begin
    sum:=0;
    for i:=1 to n do begin d[i]:=a[1,i];b[i]:=1;end;
    for j:=2 to n do begin
    min:=maxlongint;
    for i:=1 to n do
    if (d[i]<>0)and(d[i]<min) then begin min:=d[i];k:=i;end;
    sum:=sum+1;if d[k]>max then max:=d[k];d[k]:=0;
    for i:=1 to n do
    if (a[k,i]<d[i])and(i<>k) then begin d[i]:=a[k,i];b[i]:=k;end;
    end;
    end;
    begin
    readln(n,m);
    for i:=1 to n do for j:=1 to n do a[i,j]:=1000000000;
    for i:=1 to n do a[i,i]:=0;
    for i:=1 to m do begin
    readln(x,y,z);a[x,y]:=z;a[y,x]:=z;end;
    prim;
    writeln(sum,' ',max);
    end.
    秒杀,爽

  • 0
    @ 2014-10-04 17:04:04

    #include<algorithm>
    #include<iostream>
    using namespace std;
    struct q
    {
    int a,b,c;
    }p[100001];
    int f[100001];
    int c(q a,q b)
    {
    return a.c<b.c;
    }
    int find(int x)
    {
    if(f[x]!=x)
    f[x]=find(f[x]);
    return f[x];
    }
    main()
    {
    int m,n,i,x,y,k=0;
    long long s=0,t=0;
    cin>>n>>m;
    cout<<n-1<<' ';
    for(i=1;i<=n;i++)
    f[i]=i;
    for(i=1;i<=m;i++)
    cin>>p[i].a>>p[i].b>>p[i].c;
    sort(p+1,p+m+1,c);
    for(i=1;i<=m;i++)
    {
    x=find(p[i].a);
    y=find(p[i].b);
    if(x!=y)
    {
    f[x]=y;
    s+=p[i].c;
    k++;
    if(k==n-1)
    {
    cout<<p[i].c;
    return 0;
    }
    }
    }
    }

  • 0
    @ 2014-04-12 10:36:31

    #include <iostream>
    #include <algorithm>

    using namespace std;

    const int MAXN = 300;

    struct EDGE {
    int a;
    int b;
    int c;
    } w[10000];

    int n, m;
    int p[MAXN + 1];

    bool cmp(const EDGE e1, const EDGE e2)
    {
    return (e1.c < e2.c);
    }

    int find(int a)
    {
    int x = p[a];
    while (p[x] != x) x = p[x];
    return x;
    }

    void union_set(int a, int b)
    {
    a = find(a);
    b = find(b);
    p[b] = a;
    }

    int Kruskal(int & s, int & l)
    {
    int i;
    for (i = 1; i <= n; ++i) p[i] = i;

    s = l = 0;
    for (i = 1; i <= m; ++i) {
    if (find(w[i].a) != find(w[i].b)) {
    union_set(w[i].a, w[i].b);
    ++s;
    if (w[i].c > l) l = w[i].c;
    }
    }
    return 0;
    }

    int main()
    {
    cin >> n >> m;

    int i;
    for (i = 1; i <= m; ++i) cin >> w[i].a >> w[i].b >> w[i].c;

    sort(&w[1], &w[m + 1], cmp);

    int s, l;
    Kruskal(s, l);

    cout << s << " " << l;

    return 0;
    }

信息

ID
1190
难度
5
分类
树结构 | 生成树 点击显示
标签
递交数
2962
已通过
1132
通过率
38%
被复制
7
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