DP 之 poj 3616

定义:dp[i] := 在已排好序的list的第 i 次John可从Bessie获取的最大牛奶量
dp[i] = max(dp[i], myNode[i].myvalue + dp[j]);
// 条件是: myNode[j].myend + R <= myNode[i].mystart (两重循环解决)
 1 //  [4/4/2014 Sjm]
 2 #include <iostream>
 3 #include <cstdio>
 4 #include <algorithm>
 5 using namespace std;
 6 const int MAX_M = 1000, MAX_N = 1000001;
 7 int N, M, R;
 8 struct node {
 9     int mystart, myend, myvalue;
10 };
11 bool Cmp(const node n1, const node n2) {
12     if (n1.mystart == n2.mystart) return n1.myend < n2.myend;
13     else return n1.mystart < n2.mystart;
14 }
15 node myNode[MAX_M];
16 int dp[MAX_M];
17 
18 int Solve()
19 {
20     for (int i = 0; i < M; i++)
21         for (int j = 0; j < i; j++){
22             if (myNode[j].myend + R <= myNode[i].mystart){
23                 dp[i] = max(dp[i], myNode[i].myvalue + dp[j]);
24             }
25         }
26     int ans = 0;
27     for (int i = 0; i < M; i++)
28         ans = max(ans, dp[i]);
29     return ans;
30 }
31 
32 int main()
33 {
34     //freopen("input.txt", "r", stdin);
35     //freopen("output.txt", "w", stdout);
36     scanf("%d%d%d", &N, &M, &R);
37     for (int i = 0; i < M; i++) {
38         scanf("%d%d%d", &myNode[i].mystart, &myNode[i].myend, &myNode[i].myvalue);
39     }
40     sort(myNode, myNode + M, Cmp);
41     for (int i = 0; i < M; i++)
42         dp[i] = myNode[i].myvalue;
43     printf("%d
", Solve());
44     return 0;
45 }


原文地址:https://www.cnblogs.com/shijianming/p/4140867.html