Submission #19723394

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <map>
#define LL long long
#define LD long double
#define DB double
using namespace std;
const int MAXN = 2e6 + 5;
int n, ans;
int a[MAXN], b[MAXN], c[MAXN];
int d[MAXN], vis[MAXN];

int main() {
#ifdef IN
	freopen ("x.in", "r", stdin);
	freopen ("x.out", "w", stdout);
#endif
	int i,j,k;
	scanf ("%d", &n);
	for (i=1; i<=n; ++i)
		scanf ("%d%d", &a[i], &b[i]), ++c[a[i]], ++c[b[i]];
	for (i=1; i<=n; ++i) {
		if (c[ a[i] ] == 1) ++ans, d[a[i]] = vis[i] = 1;
		else if (c[ b[i] ] == 1) ++ans, d[b[i]] = vis[i] = 1;
	}
	for (i=1; i<=n; ++i)
		if (!vis[i]) {
			if (!d[ a[i] ]) ++ans, d[ a[i] ] = 1;
			else if (!d[ b[i] ]) ++ans, d[ b[i] ] = 1;
		}
	printf ("%d\n", ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:21:8: warning: unused variable ‘j’ [-Wunused-variable]
   21 |  int i,j,k;
      |        ^
./Main.cpp:21:10: warning: unused variable ‘k’ [-Wunused-variable]
   21 |  int i,j,k;
      |          ^
./Main.cpp:22:8: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf ("%d", &n);
      |  ~~~~~~^~~~~~~~~~
./Main.cpp:24:9: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   24 |   scanf ("%d%d", &a[i], &b[i]), ++c[a[i]], ++c[b[i]];
      |   ~~~~~~^~~~~~~~~~~~~~~~~~~~~~

Judge Result