1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
| #include <bits/stdc++.h>
using namespace std;
const int N = 301, M = 302;
int u, v, h[N], e[N], ne[N], idx;
int n, m;
int dp[N][M];
void add(int u, int v) {
e[++idx] = v, ne[idx] = h[u], h[u] = idx;
}
int dfs(int u) {
int sum = 2;
for (int i = h[u]; i; i = ne[i]) {
int v = e[i];
int s = dfs(v);
sum += s;
for (int j = min(m, sum); j; --j)
for (int k = 0; k < min(j, s); ++k)
dp[u][j] = max(dp[u][j], dp[v][k] + dp[u][j - k]);
}
return sum;
}
int main() {
scanf("%d%d", &n, &m);
++m;
for (int i = 1; i <= n; ++i) {
scanf("%d%d", &u, &dp[i][1]);
add(u, i);
}
dfs(0);
printf("%d\n", dp[0][m]);
return 0;
}
|