1. 程式人生 > >動態規劃之揹包問題及輸出揹包具體方案

動態規劃之揹包問題及輸出揹包具體方案

參考:https://blog.csdn.net/qq_27139155/article/details/79727991

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int N=20;
 4 int n,b;
 5 int w[N],v[N],dp[N][N];//dp[i][j]表示容量為j,有i種物品時的最大價值
 6 void dpp()
 7 {
 8     for (int i=0;i<=b;i++)//物品種數為0時
 9     {
10         dp[0][i]=0;
11     }
12     for
(int i=0;i<=n;i++)//容量為0時 13 { 14 dp[i][0]=0; 15 } 16 int ans=0,last=0,mi,mj;//mi,mj標記最大值下標 17 for (int i=1;i<=n;i++) 18 { 19 for (int j=1;j<=b;j++) 20 { 21 dp[i][j]=dp[i-1][j]; 22 if (w[i]<=j) 23 { 24 dp[i][j]=max(dp[i-1
][j-w[i]]+v[i],dp[i-1][j]);//是否放入第i種物品 25 ans=max(ans,dp[i][j]); 26 mi=i; 27 mj=j; 28 } 29 } 30 } 31 cout<<"總價值:"<<endl; 32 cout<<ans<<endl; 33 stack<int> sa; 34 for (int i=mi,j=mj;i>0
;i--)//輸出放入方案 35 { 36 if (dp[i][j]==dp[i-1][j-w[i]]+v[i]) 37 { 38 sa.push(i); 39 j=j-w[i]; 40 } 41 } 42 while (!sa.empty()) 43 { 44 cout<<"放入第"<<sa.top()<<"件物品"<<endl; 45 sa.pop(); 46 } 47 } 48 int main () 49 { 50 // freopen("in.txt","r",stdin); 51 cout<<"input the number of goods:\n"; 52 cin>>n; 53 cout<<"input the weight of every goods:\n"; 54 for (int i=1;i<=n;i++) 55 { 56 cin>>w[i]; 57 } 58 cout<<"input the value of every goods:\n"; 59 for (int i=1;i<=n;i++) 60 { 61 cin>>v[i]; 62 } 63 cout<<"input the capacity of bag:\n"; 64 cin>>b; 65 dpp(); 66 67 return 0; 68 }