Submission #55696

#	Time	Username	Problem	Language	Result	Execution time	Memory
55696		mohammad_kilani	Duathlon (APIO18_duathlon)	C++17	5 / 100	1083 ms	10204 KiB

count_triplets

#include <bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define oo 1000000000
const int N = 100010;
int n , m , u , v , needed1, needed2;
vector< int > g[N] ; 
int vis[N] ,vis2[N] , vi , vi2;

bool DFS2(int node){
    if(vis[node] == vi || vis2[node] == vi2) return false;
    if(node == needed2) return true;
    vis2[node] = vi2;
    for(int i=0;i<g[node].size();i++){
        if(DFS2(g[node][i]))
            return true;
    }
    return false;
}

bool DFS(int node){
    if(vis[node] == vi) return false;
    if(node == needed1){
        vi2++;
        return DFS2(node);
    }
    vis[node] = vi;
    for(int i=0;i<g[node].size();i++){
        if(DFS(g[node][i]))
            return true;
    }
    vis[node] = 0;
    return false;
}


int main(){
    scanf("%d%d",&n,&m);
    for(int i=0;i<m;i++){
        scanf("%d%d",&u,&v);
        g[u].push_back(v);
        g[v].push_back(u);
    }
    int ans = 0;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            for(int k=1;k<=n;k++){
                if(i == j || i == k || j == k) continue;
                needed1 = j;
                needed2 = k;
                vi++;
                if(DFS(i)){
                    ans++;
                }
            }
        }
    }
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

count_triplets.cpp: In function 'bool DFS2(int)':
count_triplets.cpp:14:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[node].size();i++){
                 ~^~~~~~~~~~~~~~~
count_triplets.cpp: In function 'bool DFS(int)':
count_triplets.cpp:28:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[node].size();i++){
                 ~^~~~~~~~~~~~~~~
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:38:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
count_triplets.cpp:40:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&u,&v);
         ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 8
• Subtask 4: 0 / 10
• Subtask 5: 0 / 13
• Subtask 6: 0 / 15
• Subtask 7: 0 / 20
• Subtask 8: 0 / 8
• Subtask 9: 0 / 10