Submission #71482085

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Source Code Expand

/* Code By WCM */
/*
Date:
大致思路：
复杂度：
期望得分：
*/
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <ctime>
#include <iomanip>
#include <vector>
#include <queue>
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define fi first
#define se second
#define pb push_back
#define int long long

using namespace std;

inline int read();
void write(int);
void writeln(int);

signed main() {

//	freopen(".in", "r", stdin);
//	freopen(".out", "w", stdout);

	int n = read(), m = read();
	vector <vector <int> > G(n + 1);
	while(m--) {
		int x = read(), y = read();
		G[y].pb(x); 
	}
	int Q = read();
	vector <bool> vis(n + 1, 0);
	queue <int> q; 
	while(Q--) {
		int op = read(), v = read();
		if(op == 1) {
			if(!vis[v]) {
				vis[v] = 1, q.push(v);
				while(!q.empty()) {
					int u = q.front(); q.pop();
					for(int vv : G[u]) if(!vis[vv]) vis[vv] = 1, q.push(vv);
				}
			}
		}
		else puts(vis[v] ? "Yes" : "No");
	}
	
//	printf("\nThe time used: ");
//	printf("%.2lfs",(double)clock()/CLOCKS_PER_SEC);

	return 0;

}

inline int read() {
	int res = 0, f = 1;
	char ch = getchar();
	while(ch < '0' || ch > '9') f = (ch == '-' ? -1 : 1), ch = getchar();
	while(ch >= '0' && ch <= '9') res = (res << 1) + (res << 3) + (ch ^ 48), ch = getchar();
	return res * f;
}

void write(int x) {
	static int sta[35];
	int top = 0;
	do { sta[top++] = x % 10, x /= 10; } while(x);
	while(top) putchar(sta[--top] ^ 48);
}

void writeln(int x) {
	write(x);
	putchar('\n');
}

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