Submission #53250821

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Source Code Expand

// LUOGU_RID: 158436210
#include<bits/stdc++.h>
#define Gc() getchar()
#define Me(x,y) memset(x,y,sizeof(x))
#define Mc(x,y) memcpy(x,y,sizeof(x))
#define d(x,y) ((m)*(x-1)+(y))
#define R(n) (rnd()%(n)+1)
#define Pc(x) putchar(x)
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define eb emplace_back
#define all(x) x.begin(),x.end()
using namespace std;using ll=long long;using db=double;using lb=long db;using ui=unsigned;using ull=unsigned long long;using pii=pair<int,int>;
const int N=400+5,M=(1<<15)+5,K=1000+5,mod=1e9+7,Mod=mod-1;const db eps=1e-8;const int INF=1e9+7;mt19937 rnd(263082);
#define Tp template<typename T>
#define Ts template<typename T,typename... Ar>
namespace Debug{
	Tp void _debug(char* f,T t){cerr<<f<<'='<<t<<endl;}
	Ts void _debug(char* f,T x,Ar... y){while(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
	#ifdef LOCAL
	#define gdb(...) _debug((char*)#__VA_ARGS__,__VA_ARGS__)
	#else 
	#define gdb(...) void()
	#endif
}using namespace Debug;
int n,m,fa[N],flag[N],in[N],vis[N];
int GF(int x){return fa[x]^x?fa[x]=GF(fa[x]):x;}
void add(int x,int y){in[x]--;in[y]++;flag[x]=flag[y]=1;fa[GF(x)]=GF(y);gdb(x,y);}
void Solve(){
	int i,j;scanf("%d%d",&n,&m);
	iota(fa+1,fa+2*m+1,1);
	while(n--){
		int a,b,c,d;scanf("%d%d%d%d",&a,&b,&c,&d);
		add(c?c+m:a,d?d:b+m);
	}
	for(i=1;i<=2*m;i++) if(flag[i]){
		if(in[i]<0){
			if(i>m){puts("NO");return;}
			vis[GF(i)]=1;
		}
		if(in[i]>0){
			if(i<=m){puts("NO");return;}
			vis[GF(i)]=1;
		}
	}
	for(i=1;i<=2*m;i++) if(flag[i]&&!vis[GF(i)]){puts("NO");return;}
	puts("YES");
}
int main(){
	int t=1;
	// scanf("%d",&t);
	while(t--) Solve();
	cerr<<clock()*1.0/CLOCKS_PER_SEC<<'\n';
}

Submission Info

Compile Error

Main.cpp: In function ‘void Solve()’:
Main.cpp:32:15: warning: unused variable ‘j’ [-Wunused-variable]
   32 |         int i,j;scanf("%d%d",&n,&m);
      |               ^
Main.cpp:32:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   32 |         int i,j;scanf("%d%d",&n,&m);
      |                 ~~~~~^~~~~~~~~~~~~~
Main.cpp:35:34: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   35 |                 int a,b,c,d;scanf("%d%d%d%d",&a,&b,&c,&d);
      |                             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Judge Result