Tree-like DP hdu1561

Some bastion hosts need to conquer another bastion host, form a forest, conquer up to M bastion hosts, and seek the greatest value of the treasures.

1. Make 0 root to form a forest tree;

2. Calculate the greatest value of the treasure that can be obtained from K bastion hosts on the current node using a backpack. However, note that the same root node cannot be placed into a backpack successively, otherwise, for example, if one node selects two or three, five are selected, that is, some nodes are repeated. Therefore, we need to put all K types in order in the J lattice of back, j --;

#include<iostream>#include<string.h>#include<stdio.h>#include<vector>using namespace std;const int maxa =  205;int dp[maxa][maxa];int back[maxa][maxa];int vis[maxa][maxa];int v[maxa];vector<int> edge[maxa];int numb[maxa];int dfs(int x, int num ){//printf("%d %d\n", x, num);    if(vis[x][num] || num == 0)        return dp[x][num];    memset(back[x], 0, sizeof(back[x]));    for(int i = 0; i < edge[x].size(); i ++){        int k = edge[x][i];//printf("%d ", k);        int last = -1;        for(int h = num-1; h >= 1; h--){            for(int j = 1; j <= h && j <= numb[k]; j++){                int a = dfs(k, j);                back[x][h] = max(back[x][h], back[x][h-j] + a);//printf("%d ", back[h]);            }//puts("");        }    }    vis[x][num] = 1;    return dp[x][num] = back[x][num-1]+v[x];}int dfs1(int x){    int sum =  0;    for(int i = 0; i < edge[x].size(); i++){        int k = edge[x][i];        sum += dfs1(k);    }    return numb[x] = sum +1;}int main(){int n, m;   //freopen("in.cpp", "r", stdin);    while(scanf("%d%d", &n, &m), n+m){        memset(vis, 0, sizeof(vis));        for(int i =0; i <= n; i++)            edge[i].clear();        for(int i =1; i <= n; i++){            int a, b;            scanf("%d%d", &a, &b);            v[i] = b;            edge[a].push_back(i);        }        dfs1(0);            memset(dp, 0, sizeof(dp));            printf("%d\n", dfs(0, m+1));           /* for(int i = 0; i <= n; i++){                printf("*%d ", numb[i]);            }*/    }}

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Tree-like DP hdu1561