# 求第五点的数据

``````#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<iostream>
#include<vector>
using namespace std;
struct BigInt{
static const int base = 100000000;
static const int width = 8;
vector<int> s;
BigInt(const int &n=0){
*this = n;
}
BigInt(const BigInt &b){
*this = b;
}
BigInt(const string &a){
*this = a;
}
BigInt& operator = (const long long &n){
long long num = n;
s.clear();
while(num>0){
s.push_back(num%base);
num /= base;
}
return *this;
}
BigInt& operator = (const BigInt &b){
s.clear();
for(int i=0; i<b.s.size(); i++){
s.push_back(b.s[i]);
}
return *this;
}
BigInt& operator = (const string &a){
s.clear();
int len = a.size(),st,ed,sum;
for(int i=len; i>=0; i -= width){
sum = 0;
ed = i;
st = max(0,i-width);
for(int j=st;j<ed;j++){
sum *= 10;
sum += a[j] - '0';
}
s.push_back(sum);
}
return *this;
}
BigInt operator + (const int & b){
return (*this)+(BigInt)b;
}
BigInt operator + (const BigInt &b){
BigInt res;
res.s.clear();
int i=0,r,c=0;
while(c!=0||i<s.size()||i<b.s.size()){
r = c;
c = 0;
if(i<s.size()) r += s[i];
if(i<b.s.size()) r += b.s[i];
res.s.push_back(r%base);
c = r/base;
i++;
}
return res;
}
BigInt operator - (const BigInt &b){
BigInt res;
res.s.clear();
int i=0,c=0,r;
while(i<s.size()){
r = c;
c = 0;
r += s[i];
if(i<b.s.size()) r -= b.s[i];
if(r<0){
c = -1;
r += base;
}
res.s.push_back(r);
i++;
}
while(res.s.size()!=1 && res.s.back()==0) res.s.pop_back();
return res;
}
BigInt operator * (const int &b){
return (*this)*(BigInt)b;
}
BigInt operator * (const BigInt &b){
BigInt res;
res.s.resize(s.size()+b.s.size(),0);
long long r;
for(int i=0;i<s.size();i++){
for(int j=0;j<b.s.size();j++){
r = (long long)s[i]*b.s[j];
res.s[i+j] += r%base;
res.s[i+j+1] += r/base;
}
}
for(int i=0;i<s.size()+b.s.size()-1;i++){
res.s[i+1] += res.s[i]/base;
res.s[i] = res.s[i]%base;
}
while(res.s.size()!=1 && res.s.back()==0) res.s.pop_back();
return res;
}
BigInt operator / (const int &b){
BigInt res = *this;
int r,c=0;
for(int i=s.size()-1;i>=0;i--){
r = c*base+res.s[i];
res.s[i] = r/b;
c = r%b;
}
while(res.s.size()!=1 && res.s.back()==0) res.s.pop_back();
return res;
}
bool operator <= (BigInt &b){
if(s.size()!=b.s.size()) return s.size()<b.s.size();
else{
for(int i=s.size()-1;i>=0;i--){
if(s[i]!=b.s[i]) return s[i]<b.s[i];
}
}
return true;
}
bool operator == (BigInt &b){
if(s.size()!=b.s.size()) return false;
else{
for(int i=s.size()-1;i>=0;i--) if(s[i]!=b.s[i]) return false;
}
return true;
}
friend ostream& operator << (ostream &out, const BigInt &b){
out<<b.s.back();
for(int i=b.s.size()-2;i>=0;i--){
char buf[20];
sprintf(buf,"%08d",b.s[i]);
for(int j=0;j<strlen(buf);j++) out<<buf[j];
}
return out;
}
};

int main(){
string a;
cin>>a;
BigInt N=a,left=0,right=N,mid,res;
while(1){
mid = (left+right)/2;
if(left == mid) break;
res = mid*mid*mid+mid*mid+mid*3;
if(res<=N) left = mid;
else right = mid;
}
cout<<left;

return 0;
}

``````

ID
1375

6

(无)

957

279

29%