@[oval_m](/user/574613) 不懂就问 memset置-1会变成什么样
by _Goodnight @ 2022-01-25 17:20:39
@[_Goodnight](/user/448910) 数组中每个数都是 -1
by Cerisier @ 2022-01-25 17:22:47
应该是的,您可以自己本地试试 qwq
by Cerisier @ 2022-01-25 17:23:22
@[oval_m](/user/574613) 你边记录端点的数组开小了?
by 「 」 @ 2022-01-25 17:25:06
这道题标号是从1开始的
by mamingxiao @ 2022-01-25 17:26:14
```cpp
for (int i = 0; i < vexnum; i++)
p[i] = i; //p[x]为节点x的父节点 没有父节点p[x]=x
```
改成
```cpp
for (int i = 1; i <= vexnum; i++)
p[i] = i; //p[x]为节点x的父节点 没有父节点p[x]=x
```
应该就可以了
by mamingxiao @ 2022-01-25 17:27:31
@[Cerisier](/user/670262) 这里memset应该会变成unsigned long long的最大值
by mamingxiao @ 2022-01-25 17:30:14
@[mamingxiao](/user/331189)
不是吧?
```cpp
#include<iostream>
#include<cstring>
using namespace std;
long long a[100010];
int main() {
memset(a, -1, sizeof(a));
cout << a[5] << endl;
return 0;
}
```
这份代码输出 -1
by Cerisier @ 2022-01-25 17:42:55
@[Cerisier](/user/670262) 我ll定义的是unsigned long long
by oval_m @ 2022-01-25 20:28:27
@[mamingxiao](/user/331189) 还是一样
by oval_m @ 2022-01-25 20:30:10