Vijos P1313 金明的预算方案（树形DP）

#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;

const int MAXD = 3210;
const int MAXN = 64;

int dp[MAXN][MAXD];
int val[MAXN], deg[MAXN], pre[MAXN];

void treedp(int u, int vol, int n)
{
if (!vol)
return ;

for (int i = 1; i <= n; ++i)
{
if (pre[i] == u)
{
for (int v = 0; v <= vol; ++v)
dp[i][v] = dp[u][v];

treedp(i, vol - val[i], n);

for (int v = vol; v >= val[i]; --v)
dp[u][v] = max(dp[u][v], dp[i][v - val[i]] + val[i] * deg[i]);
}
}
}

int main()
{
int n, vol;
while (scanf("%d %d", &vol, &n) != EOF)
{
vol /= 10;
for (int i = 1; i <= n; ++i)
scanf("%d %d %d", &val[i], °[i], &pre[i]), val[i] /= 10;

for (int v = 0; v <= vol; ++v)
dp[0][v] = 0;

treedp(0, vol, n);
printf("%d\n", dp[0][vol] * 10);
}
return 0;
}