Submission #991715

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Source Code Expand

#include <cstdio>
#include <iostream>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <vector>
#include <map>
#include <set>
#include <string>
#include <cstdlib>
#include <ctime>
#include <deque>
using namespace std;

#define N 2100000

int n, m, x, y;
vector <int> ve[N];
bool used[N];

void add(int x, int y) {
	ve[x].push_back(y);
}

void dfs(int x) {
	if (used[x])
		return ;
	used[x] = true;
	for (int i = 0; i < (int) ve[x].size(); i++)
		dfs(ve[x][i]);
}

int main() {
	scanf("%d%d", &n, &m);
	for (int i = 1; i <= n; i++) {
		scanf("%d", &x);
		while (x--) {
			scanf("%d", &y);
			add(n + y, i);
			add(i, n + y);
		}
	}
	dfs(1);
	bool ok = true;
	for (int i = 1; i <= n; i++)
		if (!used[i])
			ok = false;
	if (ok)
		printf("YES\n");
	else
		printf("NO\n");
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:34:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
                       ^
./Main.cpp:36:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &x);
                  ^
./Main.cpp:38:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &y);
                   ^

Judge Result