#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
const int maxn = 100000 + 10;
int f[maxn];
int find(int x) {
return f[x] != x ? f[x] = find(f[x]) : x;
}
int main() {
int x, y;
while(scanf("%d", &x) == 1) {
for(int i = 0; i <= maxn; i++) {
f[i] = i;
}
int refuse_num = 0;
while(x != -1) {
scanf("%d", &y);
x = find(x); y = find(y);
if(x == y) {
++ refuse_num;
}
else{
f[x] = y;
}
scanf("%d", &x);
}
printf("%d\n", refuse_num);
}
}
易炸物LA3644(并查集)
最新推荐文章于 2022-11-11 07:50:09 发布