采药 水题 dp 01背包问题 luogu1048

 1 #include <cstdio>
 2 #include <cstring>
 3 #include <algorithm>
 4 
 5 const int maxn = 1000 + 500;
 6 int dp[maxn];
 7 int t, m;
 8 int s1, v1;
 9 
10 int main () {
11     scanf("%d %d", &t, &m);
12     for (int i = 1; i <= m; i++) {
13         scanf("%d %d", &s1, &v1);
14         for (int j = t; j >= s1; j--) {
15             dp[j] = std :: max(dp[j], dp[j - s1] + v1);
16         }
17     }
18     int ans = 0;
19     for (int i = 0; i <= t; i++) ans = std :: max(ans, dp[i]);
20     printf("%d", ans);
21     return 0;
22 }