Submission #2203331

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Source Code Expand

#include <iostream>
#include <queue>
#include <vector>
using namespace std;
#define debug(x) std::cerr << #x << " = " << (x) << std::endl
typedef long long LL;
const int MAXN = 1e5+17;
int a[MAXN],b[MAXN];
int main(int argc ,char const *argv[])
{
    #ifdef noob
    freopen("Input.txt","r",stdin);freopen("Output.txt","w",stdout);
    #endif
    int n,m;
	cin>>n>>m;
	for (int i = 0; i < m; ++i)
	{
		int u,v;
		cin>>u>>v;
		u--;v--;
		a[u]++,a[v]--;
	}
	int now = 0;
	for (int i = 0; i < n; ++i)
	{
		// debug(i);
		// debug(a[i]);
		// debug(now);
		now+=a[i];
		b[i]+=now;
	}
	bool can = true;
	for (int i = 0; i < n-1; ++i)
	{
		// debug(i);
		// debug(b[i]);
		if(b[i]&1) can = false;
	}
	if(can) cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
    return 0;        

}

Submission Info

Judge Result