hdu_4707

算是水题一道吧，我也没有建树，看别人又用vector,又用bfs，dfs的，对vector不熟，所以就模拟了一下

#include<iostream>
#include<string.h>
#include<cstdio>
using namespace std;
int a[100005];
int main()
{
int t;cin>>t;
while(t--)
{
int n,k,p,q;
cin>>n>>k;
a[0]=0;
memset(a,0,sizeof(a));
for(int i=0;i<n-1;i++)
{
scanf("%d%d",&p,&q);
a[q]=a[p]+1;
}
p=0;
for(int i=0;i<n;i++)
if(a[i]>k)
p++;
cout<<p<<endl;
}
return 0;
}

附上别人的代码

#include <cstdio>
#include <cstring>

using namespace std;

const int maxn = 100000 + 10;

int D, head[maxn], nxt[maxn<<1], v[maxn<<1], ecnt, d[maxn], ret;

void init(){
memset(head, -1, sizeof(head));
ecnt = 0;
ret = 0;
}

void addEdge(int uu, int vv){
v[ecnt] = vv;
nxt[ecnt] = head[uu];
head[uu] = ecnt;
ecnt++;
}

void dfs(int x, int fa){
if(d[x] > D) ret++;
for(int e = head[x]; e != -1; e = nxt[e]) if(v[e] != fa){
d[v[e]] = d[x] + 1;
dfs(v[e], x);
}
}

void solve(){
d[0] = 0;
dfs(0, -1);
printf("%d\n", ret);
}

int main()
{
int T, N, uu, vv;
scanf("%d", &T);
while(T--){
init();
scanf("%d%d", &N, &D);
for(int i = 0; i < N-1; i++){
scanf("%d%d", &uu, &vv);
addEdge(uu, vv);
addEdge(vv, uu);
}
solve();
}
return 0;
}