Submission #1197466

#	Time	Username	Problem	Language	Result	Execution time	Memory
1197466		hackstar	Duathlon (APIO18_duathlon)	C++20	0 / 100	670 ms	1114112 KiB

count_triplets

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include<bits/stdc++.h>

using namespace std;
using namespace __gnu_pbds;

template <typename T>
using ordered_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
template <typename T>
using ordered_multiset = tree<T,null_type,less_equal<T>,rb_tree_tag,tree_order_statistics_node_update>;

#pragma GCC optimize("Ofast,O3,unroll-loops")
#pragma GCC target("avx,avx2")

#define int long long
#define ll long long
#define pii pair<int,int>
#define ff first
#define ss second
#define vi vector<int>
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()

template<typename T1,typename T2>
istream& operator>>(istream& cin,pair<T1,T2>& s){
	cin>>s.first>>s.second;
	return cin;
}
template<typename T1,typename T2>
ostream& operator<<(ostream& cout,pair<T1,T2>& s){
	cout<<s.first<<' '<<s.second<<'\n';
	return cout;
}
template<typename T>
istream& operator>>(istream& cin,vector<T>& a){
	for(T& x:a){
		cin>>x;
	}
	return cin;
}
template<typename T>
ostream& operator<<(ostream& cout,vector<T>& a){
	for(T& x:a){
		cout<<x<<' ';
	}
	return cout;
}

const int inf=1e18;


void solve(){
	int n,m;
	cin>>n>>m;
	vector<vector<int>>g(n);
	for(int i=0;i<m;i++){
		int u,v;
		cin>>u>>v;
		u--,v--;
		g[u].emplace_back(v);
		g[v].emplace_back(u);
	}
	int ans=0;
	vector<int>dp(n);
	auto dfs=[&](auto dfs,int u,int p=-1)->void{
		for(int v:g[u]){
			if(u==p){
				continue;
			}
			dp[v]=dp[u]+1;
			dfs(dfs,v,u);
		}
		ans+=max(0ll,dp[u]-2);
	};
	for(int i=0;i<n;i++){
		fill(all(dp),1);
		dfs(dfs,i);
	}
	cout<<ans;
}

signed main(){
	cin.tie(nullptr)->sync_with_stdio(false);
	int t=1;
	#ifdef LOCAL
		freopen("input.txt", "r", stdin);
		freopen("output.txt", "w", stdout);
	#endif
	//cin>>t;
	while(t--){
		solve();
	}
}

• 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