Submission #698732

#	Time	Username	Problem	Language	Result	Execution time	Memory
698732		vjudge1	Duathlon (APIO18_duathlon)	C++17	10 / 100	1098 ms	10528 KiB

count_triplets

#include <bits/stdc++.h>
#include <array>
#define all(v) (v.begin()), (v.end())
#define setall(a, val) for(auto& x : a) x = val
#define ll long long
clock_t start_time;
double get_time() { return (double)(clock() - start_time) / CLOCKS_PER_SEC; }
void init() {
#ifndef ONLINE_JUDGE
	FILE* _ = freopen("in.txt", "r", stdin);
	start_time = clock();
#endif
}
const ll MOD = 998244353;
const ll N = 1e5 + 1;
const ll M = 2e2 + 1;
using namespace std;
//####################################################################################

bool vis[N];
int ans = 0;
vector< vector<int> > v;
void dfs(int cur, int dst) {
	vis[cur] = 1;
	if (dst > 1)
		ans += dst - 1;

	for (int nxt : v[cur]) {
		if (!vis[nxt])
			dfs(nxt, dst + 1);
	}
	vis[cur] = 0;
}

int main() {
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); srand(time(0)); //init();

	int n, m;
	cin >> n >> m;
	v.resize(n + 1);
	for (int i = 0; i < m; i++) {
		int a, b;
		cin >> a >> b;
		v[a].push_back(b);
		v[b].push_back(a);
	}

	for (int i = 1; i <= n; i++) {
		setall(vis, 0);
		dfs(i, 0);
	}
	cout << ans << endl;

	cerr << get_time() << "s" << endl;
}

Compilation message (stderr)

count_triplets.cpp: In function 'void init()':
count_triplets.cpp:10:8: warning: unused variable '_' [-Wunused-variable]
   10 |  FILE* _ = freopen("in.txt", "r", stdin);
      |        ^

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