Submission #518977

#	Time	Username	Problem	Language	Result	Execution time	Memory
518977		mansur	Duathlon (APIO18_duathlon)	C++17	5 / 100	1079 ms	460 KiB

count_triplets

#include<bits/stdc++.h>	
 
//01001101 01100001 01101011 01101000 01100001  01100111 01100001 01111001 

using namespace std;

#define all(a) a.begin(), a.end()                                                   
#define rall(a) a.rbegin(), a.rend()
#define ll long long
#define pb push_back
#define sz(a) a.size()
#define nl '\n'
#define popb pop_back()                                                                   
#define ld double
#define ull unsigned long long
#define ff first                                         
#define ss second  
#define fix fixed << setprecision
#define pii pair<int, int>                          
#define E exit (0)
#define int long long                    
 
const int inf = 1e15, N = 1e6, mod = 998244353;                    

double eps = 1e-6;

vector<pii> dir = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

int cur, was;

vector<int> adj[51];

void dfs(int u, int f) {
	was ^= (1ll << u);
	if (u == f) {
		cur |= was;
		was ^= (1ll << u);
		return;
	}
	for (auto e: adj[u]) {
		if (was >> e & 1) continue;
		dfs(e, f);
	}
	was ^= (1ll << u);
}

main() {                                                         
	//freopen("F.in", "r", stdin);                                                                                     
	//freopen("F.out", "w", stdout);                                                                                     
	ios_base::sync_with_stdio(NULL);                                                                                        
	cin.tie(NULL);
	int n, m;
	cin >> n >> m;
	for (int i = 1; i <= m; i++) {
		int u, v;
		cin >> u >> v;
		adj[u].pb(v);
		adj[v].pb(u);
	}
	int ans = 0;
	for (int s = 1; s <= n; s++) {
		for (int f = 1; f <= n; f++) {
			if (s == f) continue;
			dfs(s, f);
			ans += max(0, __builtin_popcountll(cur) - 2);
			cur = 0;
		}
	}
	cout << ans;
}
                                                                           

Compilation message (stderr)

count_triplets.cpp:47:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   47 | main() {
      | ^~~~

• 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