#include <stdio.h>
#include <stdbool.h>
int d[501][501];
bool visit[501];
int main(void) {
int n, m;
while (m--) {
int x, y;
d[x][y] = 1;
d[y][x] = 1;
}
int ans = 0;
for (int i = 1; i <= n; i++) {
if (d[1][i] == 1 && visit[i] == false) {
ans += 1;
visit[i] = true;
for (int j = 1; j <= n; j++) {
if (d[i][j] == 1 && visit[j] == false) {
ans += 1;
visit[j] = true;
}
}
}
}
return 0;
}
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