Submission #4675666

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Source Code Expand

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define LL long long
#define FOR(i,a,b) for (int i=a;i<=b;++i)
#define FORD(i,a,b) for (int i=a;i>=b;--i)
using namespace std;
typedef pair<LL,LL> pa;
typedef long double ld;
void getint(int &v){
    char ch,fu=0;
    for(ch='*'; (ch<'0'||ch>'9')&&ch!='-'; ch=getchar());
    if(ch=='-') fu=1, ch=getchar();
    for(v=0; ch>='0'&&ch<='9'; ch=getchar()) v=v*10+ch-'0';
    if(fu) v=-v;
}
bool u[500010];
int nedge,ap[500010],too[500010],top,n,m,D,S,d[500010],x,y,tp,stk[500010],hed[500010],nxt[500010];
void ae(int x,int y){
	nxt[++nedge]=hed[x];
	hed[x]=nedge;
	too[nedge]=y;
}
void dfs(int x){
	for (int i=hed[x];i;i=hed[x]){
		hed[x]=nxt[i];
		if (u[i]) continue;
		u[i]=u[i^1]=1;
		int y=too[i];
		dfs(y);
	}
	stk[++top]=x;
}
int main(){
	scanf("%d%d",&n,&m);
	if (n==1) return puts("No"),0;
	nedge=1;
	FOR(i,1,m){
		getint(x),getint(y);
		ae(x,y),ae(y,x);
		++d[x],++d[y];
	}
	FOR(i,1,n) if (d[i]&1) return puts("No"),0;
	FOR(i,1,n) if (d[i]>=6) return puts("Yes"),0;
	S=1;
	dfs(S);
	--top;
	assert((top==m));
//	FORD(i,top,1) printf("%d ",stk[i]);
	reverse(stk+1,stk+top+1);
	FOR(i,top+1,top+top) stk[i]=stk[i-top];
	memset(nxt,0,sizeof(nxt));
	FOR(i,1,n) ap[i]=top+top+1;
	nxt[top+top+1]=top*10+10;
	FORD(i,top+top,1){
		int t=ap[stk[i]];
		nxt[i]=min(nxt[i+1],t);
		if (i<=top && ap[stk[i]]<top+i-1){
			if (nxt[ap[stk[i]]+1]<=top+i-1){
				return puts("Yes"),0;
			}
		}
		ap[stk[i]]=i;
	}
	puts("No");
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:37:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^

Judge Result