Submission #71951

#	Time	Username	Problem	Language	Result	Execution time	Memory
71951		KLPP	Duathlon (APIO18_duathlon)	C++14	23 / 100	272 ms	53904 KiB

count_triplets

#include<iostream>
#include<stdio.h>
#include<vector>
#include<queue>
#include<algorithm>

using namespace std;
typedef long long int lld;
lld DP[1000000];
bool visited[1000000];
vector<int>nei[1000000];
lld ans;
bool visited2[1000000];
void DFS(int node,lld dist){//cout<<node+1<<" "<<dist<<endl;
	visited[node]=true;
	lld sum=0;
	//lld square=0;
	//lld totaldist=0;
	for(int i=0;i<nei[node].size();i++){
		int v=nei[node][i];
		if(!visited[v]){
			DFS(v,dist+1);
			sum+=DP[v];
			//square+=DP[v]*DP[v];
		}
	}
	DP[node]=sum+1;
	//ans+=sum*sum-square;
	//cout<<sum*sum-square<<" "<<node+1<<endl;
	//ans+=dist*(dist-1);
}
void DFS2(int node,lld componentsize){
	visited2[node]=true;
	lld sq=componentsize-DP[node];
	sq*=sq;
	for(int i=0;i<nei[node].size();i++){
		int v=nei[node][i];
		if(!visited2[v]){
			DFS2(v,componentsize);
			sq+=DP[v]*DP[v];
		}		
	}
	ans+=(componentsize-1)*(componentsize-1)-sq;
	//cout<<(componentsize-1)*(componentsize-1)-sq<<" "<<node+1<<endl;
}
int main(){
	int n,m;
	cin>>n>>m;
	for(int i=0;i<m;i++){
		int x,y;
		cin>>x>>y;
		x--;y--;
		nei[x].push_back(y);
		nei[y].push_back(x);
	}
	ans=0;
	for(int i=0;i<n;i++){
		DP[i]=-1;
		visited[i]=false;
		visited2[i]=false;
	}
	for(int i=0;i<n;i++){
		if(!visited[i]){
			DFS(i,0);
			DFS2(i,DP[i]);
		}
	}//for(int i=0;i<n;i++)cout<<DP[i]<<" "<<i+1<<endl;
	cout<<ans<<endl;

	return 0;	
}

Compilation message (stderr)

count_triplets.cpp: In function 'void DFS(int, lld)':
count_triplets.cpp:19:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<nei[node].size();i++){
              ~^~~~~~~~~~~~~~~~~
count_triplets.cpp: In function 'void DFS2(int, lld)':
count_triplets.cpp:36:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<nei[node].size();i++){
              ~^~~~~~~~~~~~~~~~~

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