bzoj 3573: [Hnoi2014]米特运输

 1 #include <bits/stdc++.h>
 2 #define LL long long
 3 #define lowbit(x) x&(-x)
 4 #define inf 0x3f3f3f3f
 5 #define eps 1e-5
 6 #define N 100005
 7 using namespace std;
 8 inline int ra()
 9 {
10     int x=0,f=1; char ch=getchar();
11     while (ch<‘0‘ || ch>‘9‘) {if (ch==‘-‘) f=-1; ch=getchar();}
12     while (ch>=‘0‘ && ch<=‘9‘) {x=x*10+ch-‘0‘; ch=getchar();}
13     return x*f;
14 }
15 int n,cnt;
16 double a[500005],s[500005],val[500005];
17 int d[500005],head[500005];
18 struct edge{
19     int to,next;
20 }e[1000005];
21 void insert(int x, int y){
22     e[++cnt].next=head[x]; e[cnt].to=y; head[x]=cnt;
23 }
24 void dfs(int x, int fa)
25 {
26     for (int i=head[x];i;i=e[i].next)
27         if (e[i].to!=fa)
28         {
29             s[e[i].to]=s[x]+log(d[x]);
30             dfs(e[i].to,x);
31         }
32 }
33 int main(int argc, char const *argv[])
34 {
35     n=ra();
36     for (int i=1; i<=n; i++) a[i]=ra();
37     for (int i=1; i<n; i++)
38     {
39         int x=ra(),y=ra();
40         insert(x,y); insert(y,x);
41         d[x]++; d[y]++;
42     }
43     for (int i=2; i<=n; i++) d[i]--;
44     s[1]=log(1);
45     dfs(1,0);
46     for (int i=1; i<=n; i++) val[i]=s[i]+log(a[i]);
47 //    for (int i=1; i<=n; i++)
48 //        printf("%.2lf\n",val[i]);
49     sort(val+1,val+n+1);
50     int ans=0,tmp=1;
51     for (int i=2; i<=n; i++)
52         if (val[i]-val[i-1]<eps) tmp++;
53             else ans=max(ans,tmp),tmp=1;
54     ans=max(ans,tmp);
55     cout<<n-ans;
56     return 0;
57 }