/in/foo.cc:16:1: error: 'vector' does not name a type
 vector<ll>arv[maxn];
 ^~~~~~
/in/foo.cc: In function 'void bfs()':
/in/foo.cc:24:5: error: 'queue' was not declared in this scope
     queue<int>q;
     ^~~~~
/in/foo.cc:24:11: error: expected primary-expression before 'int'
     queue<int>q;
           ^~~
/in/foo.cc:28:9: error: 'q' was not declared in this scope
         q.push(y);
         ^
/in/foo.cc:33:12: error: 'q' was not declared in this scope
     while(!q.empty()) {
            ^
/in/foo.cc: In function 'bool solve(ll)':
/in/foo.cc:66:29: error: 'memset' was not declared in this scope
     memset(vis,0,sizeof(vis));
                             ^
/in/foo.cc:71:15: error: 'arv' was not declared in this scope
         while(arv[i].size()) arv[i].pop_back();
               ^~~
/in/foo.cc:90:13: error: 'arv' was not declared in this scope
             arv[j].push_back(T-d[i]);
             ^~~
/in/foo.cc:100:16: error: 'arv' was not declared in this scope
             if(arv[i].size()>0&&arv[i][arv[i].size()-1]<z*2) arv[i].pop_back();
                ^~~
/in/foo.cc:103:24: error: 'arv' was not declared in this scope
         for(int j=0; j<arv[i].size(); j++) {
                        ^~~
/in/foo.cc:108:19: error: 'sort' was not declared in this scope
     sort(f+1,f+p+1);
                   ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:118:32: error: 'memset' was not declared in this scope
     memset(head,-1,sizeof(head));
                                ^