Java版本
具体思路就是构造物品类,然后对主件判断是否有附件,若有附件则依次添加,根据主件、附件1、附件2的组合有四种情况
- 只有主件
- 主件+附件1
- 主件+附件2
- 主件+附件1+附件2
根据以上情况转化问题为经典的 01背包问题 ,接着就是套公式动态规划即可
该题解参考了博客园舞动的心的算法笔记,原帖地址 算法笔记_103:蓝桥杯练习 算法提高 金明的预算方案(Java)
代码完全AC import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int money = sc.nextInt(); int n = sc.nextInt(); if(n<=0||money<=0) System.out.println(0); good[] Gs = new good[n+1]; for (int i = 1; i <= n; i++) { int v = sc.nextInt(); int p = sc.nextInt(); int q = sc.nextInt(); Gs[i] = new good(v,p,q); if(q>0){ if(Gs[q].a1==0){ Gs[q].setA1(i); }else { Gs[q].setA2(i); } } } int[][] dp = new int[n+1][money+1]; for (int i = 1; i <= n; i++) { int v=0,v1=0,v2=0,v3=0,tempdp=0,tempdp1=0,tempdp2=0,tempdp3=0; v = Gs[i].v; tempdp = Gs[i].p*v; //只有主件 if(Gs[i].a1!=0){//主件加附件1 v1 = Gs[Gs[i].a1].v+v; tempdp1 = tempdp + Gs[Gs[i].a1].v*Gs[Gs[i].a1].p; } if(Gs[i].a2!=0){//主件加附件2 v2 = Gs[Gs[i].a2].v+v; tempdp2 = tempdp + Gs[Gs[i].a2].v*Gs[Gs[i].a2].p; } if(Gs[i].a1!=0&&Gs[i].a2!=0){//主件加附件1和附件2 v3 = Gs[Gs[i].a1].v+Gs[Gs[i].a2].v+v; tempdp3 = tempdp + Gs[Gs[i].a1].v*Gs[Gs[i].a1].p + Gs[Gs[i].a2].v*Gs[Gs[i].a2].p; } for(int j=1; j<=money; j++){ if(Gs[i].q > 0) { //当物品i是附件时,相当于跳过 dp[i][j] = dp[i-1][j]; } else { dp[i][j] = dp[i-1][j]; if(j>=v&&v!=0) dp[i][j] = Math.max(dp[i][j],dp[i-1][j-v]+tempdp); if(j>=v1&&v1!=0) dp[i][j] = Math.max(dp[i][j],dp[i-1][j-v1]+tempdp1); if(j>=v2&&v2!=0) dp[i][j] = Math.max(dp[i][j],dp[i-1][j-v2]+tempdp2); if(j>=v3&&v3!=0) dp[i][j] = Math.max(dp[i][j],dp[i-1][j-v3]+tempdp3); } } } System.out.println(dp[n][money]); } /** * 定义物品类 */ private static class good{ public int v; //物品的价格 public int p; //物品的重要度 public int q; //物品的主附件ID public int a1=0; //附件1ID public int a2=0; //附件2ID public good(int v, int p, int q) { this.v = v; this.p = p; this.q = q; } public void setA1(int a1) { this.a1 = a1; } public void setA2(int a2) { this.a2 = a2; } } }