Submission #1234302

#	Time	Username	Problem	Language	Result	Execution time	Memory
1234302		Jer	Duathlon (APIO18_duathlon)	C++20	0 / 100	1119 ms	1114112 KiB

count_triplets

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int MAXN = 100005;
const int LOG = 20;

vector<int> con[MAXN];

int n, m;
ll res = 0;

int dfs(int curr, int par)
{
    int sub = 0;
    for (auto i : con[curr])
    {
        if (i == par)
            continue;
        sub += dfs(i, curr);
    }

    res += (ll)(n - sub - 1) * (ll)(sub);

    return sub + 1;
}

int main()
{
    scanf("%d%d", &n, &m);
    int a, b;

    for (int i = 0; i < m; ++i)
        scanf("%d%d", &a, &b), con[a].push_back(b), con[b].push_back(a);

    for (auto i : con[1])
        dfs(i, 1);

    printf("%lld\n", 2LL * res);

    return 0;
}

Compilation message (stderr)

count_triplets.cpp: In function 'int main()':
count_triplets.cpp:32:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     scanf("%d%d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~
count_triplets.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         scanf("%d%d", &a, &b), con[a].push_back(b), con[b].push_back(a);
      |         ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 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