Question

Shopping Spree:

Acme Super Store is having a contest to give away shopping sprees to lucky families. If a family wins a shopping spree each person in the family can take any items in the store that he or she can carry out, however each person can only take one of each type of item. For example, one family member can take one television, one watch and one toaster, while another family member can take one television, one camera and one pair of shoes. Each item has a price (in dollars) and a weight (in pounds) and each person in the family has a limit in the total weight they can carry. Two people cannot work together to carry an item. Your job is to help the families select items for each person to carry to maximize the total price of all items the family takes. Write an algorithm to determine the maximum total price of items for each family and the items that each family member should select.

a) A verbal description and give pseudo-code for your algorithm. Try to create an algorithm that is efficient in both time and storage requirements.

b) Implement your algorithm by writing a program named “shopping.cpp” (in C++) .

Input: The input file named “shopping.txt” consists of T test cases

* T (1 ≤ T ≤ 100) is given on the first line of the input file.

* Each test case begins with a line containing a single integer number N that indicates the number of items (1 ≤ N ≤ 100) in that test case

* Followed by N lines, each containing two integers: P and W. The first integer (1 ≤ P ≤ 5000) corresponds to the price of object and the second integer (1 ≤ W ≤ 100) corresponds to the weight of object.

* The next line contains one integer (1 ≤ F ≤ 30) which is the number of people in that family.

* The next F lines contains the maximum weight (1 ≤ M ≤ 200) that can be carried by the ith person in the family (1 ≤  i ≤ F).

Output: Written to a file named “results.txt”. For each test case your program should output the maximum total price of all goods that the family can carry out during their shopping spree and for each the family member, numbered 1 ≤ i ≤ F, list the item numbers 1 ≤ N ≤ 100 that they should select.

Sample Input
2
3
72 17
44 23
31 24
1
26
6
64 26
85 22
52 4
99 18
39 13
54 9
4
23
20
20
36

Sample Output:
Test Case 1
Total Price 72
Member Items
1: 1
Test Case 2
Total Price 568
Member Items

1: 3 4
2: 3 6
3: 3 6

4: 3 4 6

Answer 1

#include <string.h>
#include <iostream>
using namespace std;
void reverseString(string& str)
{ int n = str.length();
// Swap character starting from two
// corners
for (int i = 0; i < n / 2; i++)
swap(str[i], str[n - i - 1]);
}
string* knapSack(int W, int wt[], int val[], int n,int count) /*return type is string because we have to return two value one is max value and second is index of weights*/
{
int i, w;
int K[n+1][W+1];
string s="";
static string a[2];
// Build table K[][] in bottom up manner
for (i = 0; i <= n; i++)
{
for (w = 0; w <= W; w++)
{
if (i==0 || w==0)
{
K[i][w] = 0;
}
else if (wt[i-1] <= w)
{
K[i][w] = max(val[i-1] + K[i-1][w-wt[i-1]], K[i-1][w]);
}   
else
{
K[i][w] = K[i-1][w];
}
}
}

int res = K[n][W];
w = W;
for (i = n; i > 0 && res > 0; i--) {
/* either the result comes from the top (K[i-1][w]) or from (val[i-1] + K[i-1] [w-wt[i-1]]) as in Knapsack table. If it comes from the latter one/ it means the item is included. */
if (res == K[i - 1][w])
continue;   
else {
// This item is included.
s+=to_string(i);
s+=" ";
// Since this weight is included its
// value is deducted
res = res - val[i - 1];
w = w - wt[i - 1];
}
}

reverseString(s); //reverse the string

a[0]=to_string(count);//famly member index
a[0]+=" :";
a[0]+=s;
a[1]=to_string(K[n][W]);// max value
return a;
}
int main() {
int t;
cin>>t;
int c;
c=1;
while(t!=0)
{
int n;
cin>>n;
int val[100];
int weigth[100];
for(int i=0;i<n;i++)
{
cin>>val[i]>>weigth[i];
}
int familyperson;
cin>>familyperson;
int total;
total=0;
string a[30];
for(int i=0;i<familyperson;i++)
{
int W;
cin>>W;
string* p=knapSack(W,weigth,val,n,i+1);
a[i]=p[0];
total+=stoi(p[1]);
}
cout<<"Test Case "<<c<<endl;
c++;
cout<<"Total Price "<<total<<endl;
cout<<"Member Items"<<endl;
for(int z=0;z<familyperson;z++)
{
cout<<a[z]<<endl;
}
t--;
}
return 0;
}
/*

Input :-

2
3
72 17
44 23
31 24
1
26
6
64 26
85 22
52 4
99 18
39 13
54 9
4
23
20
20
36

Output:

Test Case 1
Total Price 72
Member Items
1 : 1
Test Case 2
Total Price 568
Member Items
1 : 3 4
2 : 3 6
3 : 3 6
4 : 3 4 6

*/