Submission #991940

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Source Code Expand

#include <iostream>
#include <fstream>
#include <sstream>

#include <vector>
#include <set>
#include <bitset>
#include <map>
#include <deque>
#include <string>

#include <algorithm>
#include <numeric>

#include <cstdio>
#include <cassert>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <cmath>

#define pb push_back
#define pbk pop_back
#define mp make_pair
#define fs first
#define sc second
#define all(x) (x).begin(), (x).end()
#define foreach(i, a) for (__typeof((a).begin()) i = (a).begin(); i != (a).end(); ++i)
#define len(a) ((int) (a).size())

#ifdef CUTEBMAING
#define eprintf(...) fprintf(stderr, __VA_ARGS__)
#else
#define eprintf(...) 42
#endif

using namespace std;

typedef long long int64;
typedef long double ld;
typedef unsigned long long lint;

const int inf = (1 << 30) - 1;
const int64 linf = (1ll << 62) - 1;
const int N = 1e6 + 100;

int n, m;
vector<int> a[N];
vector<int> g[N];

bool used[N];

void dfs(int v) {
    if (used[v]) {
        return ;
    }
    used[v] = true;
    for (int i : g[v]) {
        dfs(i);
    }
}

int main() {
#ifdef XCODE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        int len; scanf("%d", &len);
        for (int j = 0; j < len; j++) {
            int x; scanf("%d", &x), x--;
            a[x].pb(i);
        }
    }
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < len(a[i]) - 1; j++) {
            g[a[i][j]].pb(a[i][j + 1]);
            g[a[i][j + 1]].pb(a[i][j]);
        }
    }
    dfs(0);
    for (int i = 0; i < n; i++) {
        if (!used[i]) {
            puts("NO");
            return 0;
        }
    }
    puts("YES");
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:70:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         int len; scanf("%d", &len);
                                   ^
./Main.cpp:72:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
             int x; scanf("%d", &x), x--;
                                        ^

Judge Result