【HDU 5326 WORK】

WORK

Problem Description

It’s an interesting experience to move from ICPC to work, end my college life and start a brand new journey in company.
As is known to all, every stuff in a company has a title, everyone except the boss has a direct leader, and all the relationship forms a tree. If A’s title is higher than B(A is the direct or indirect leader of B), we call it A manages B.
Now, give you the relation of a company, can you calculate how many people manage k people.

Input
There are multiple test cases.
Each test case begins with two integers n and k, n indicates the number of stuff of the company.
Each of the following n-1 lines has two integers A and B, means A is the direct leader of B.

1 <= n <= 100 , 0 <= k < n
1 <= A, B <= n

Output
For each test case, output the answer as described above.

Sample Input
7 2
1 2
1 3
2 4
2 5
3 6
3 7

Sample Output
2

#include<cstdio>#define K 1011int st[K];int pa[K];void find(int p){    while(p!=st[p])    {        p=st[p];        pa[p]++;    }}int main(){    int n,m,i,a,b,ans;    while(~scanf("%d%d",&n,&m))    {        for(i=1;i<=n;i++)        {            st[i]=i;            pa[i]=0;        }        for(i=1;i<n;i++)        {            scanf("%d%d",&a,&b);            st[b]=a;        }        ans=0;        for(i=1;i<=n;i++)        {            find(i);        }        for(i=1;i<=n;i++)        {            if(pa[i]==m)            ans++;        }        printf("%d\n",ans);    }    return 0;}