Prom without a boss (HDU 1520)

Title Description Description

Ural University has a staff of N and is numbered 1~n. They have affiliation, which means that their relationship is like a tree rooted in the headmaster, and the parent node is the direct boss of the child node. Each employee has a happiness index. There is now an anniversary party, which asks the staff to have the most happiness index. However, no staff is willing to attend with the direct boss.

Enter a description Input Description

The first line is an integer n. (1<=n<=6000)
Next n lines, line i+1 represents the happiness index RI for staff i. ( -128<=ri<=127)
Next N-1 line, enter a pair of integer l, K for each line. Indicates that K is the direct boss of L.
Last line input 0, 0.

Output description Output Description

Output the maximum happiness index.

Sample input Sample Input

7
1
1
1
1
1
1
1
1 3
2 3
6 4
7 4
4 5
3 5
0 0

Sample output Sample Output

5

Data range and Tips Data Size & Hint

Each test point 1s

/*tree-shaped DP*/#include<cstdio>#include<iostream>#include<cstring>#include<vector>#defineM 6010using namespacestd;intVis[m],inch[m],f[m][2],n;vector<int>G[m];voidDfsintx) {    if(Vis[x])return; VIS[X]=1;  for(intI=0; I<g[x].size (); i++)    {        inty=G[x][i];        DFS (y); f[x][0]+=max (f[y][0],f[y][1]); f[x][1]+=f[y][0]; }}voidinit () { for(intI=1; i<=n;i++) scanf ("%d", &f[i][1]);  while(1)    {        intx, y; scanf ("%d%d",&x,&y); if(x==0&&y==0) Break;        G[y].push_back (x); inch[x]++; }    intp=0;  for(intI=1; i<=n;i++)      if(!inch[i]) {p=i;          DFS (i);  Break; } printf ("%d\n", Max (f[p][0],f[p][1]));  for(intI=1; i<=n;i++) G[i].clear ();}intMain () { while(SCANF ("%d", &n) = =1) {memset (inch,0,sizeof(inch)); Memset (F,0,sizeof(f)); memset (Vis,0,sizeof(VIS));    Init (); }}

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Prom without a boss (HDU 1520)