|Hdu 1561|动态规划|The more, The Better

http://acm.hdu.edu.cn/showproblem.php?pid=1561

此题与选课一题一样，讲解看

http://blog.csdn.net/Darost/article/details/52555114

#include<cstdio>#include<cstring>#include<algorithm>#include<vector>#define ms(i,j) memset(i, j, sizeof(i));using namespace std;int n,m;int c[205];vector<int> G[205];int f[205][205];int t;void dfs(int u){for (int i=1;i<=m;i++)f[u][i] = c[u];for (int i=0;i<G[u].size();i++){int v = G[u][i];dfs(v);for (int j=t;j>=2;j--)for (int k=1;k<j;k++)f[u][j] = max(f[u][j], f[u][j-k]+f[v][k]);}}int main(){while (scanf("%d%d", &n, &m)==2&&(n||m)){for (int i=0;i<=n;i++) G[i].clear();ms(f,0); for (int i=1;i<=n;i++){int ai;scanf("%d%d", &ai, &c[i]);G[ai].push_back(i);}t = m+1;dfs(0);printf("%d\n", f[0][m+1]);} return 0;}