Question

help please!! due today!!

Answer 1

We are considering that we have to take full item (not its some part) : (0/1 knapsack )

Greedy approach to solve this is :

Consider all subsets of the items and calculate the total weight and value of all subsets. We will consider only those subsets whose total weight is smaller than W. From all such subsets, pick the maximum value subset.

Algorithm :

Input : W is max weight possible

item[] : It is an structure array . It has two parts :

item.v = it's value ; item.w = it's weight

1. Get the max no. of subsets possible

max_no_of_subsets = pow (2 , no_of_items)

2. Assign the result to zero

result = 0

3. Loop for counter from 0 to max_no_of_subsets

a) Assign the temporary variable to use them

present_weight = 0;

present_value = 0

(b) Loop for i = 0 to no_of_items

i) if ith bit is set in counter

present_weight = present_weight + item[i].w;

  present_value = present_value + item[i].v;

(c) If present_weight is less than max_weight_possible, then update result i.e.

if (( present_weight <= W ) && (result < current_result))

result = current_result

4. return the value of result // It is the answer

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Solution to your problem :

We have 5 items . So max no. of subsets = 32;

Answer for your problem is : 21

------------------------

Code :

---------------

#include <iostream>

using namespace std;

struct item

{

int v;

int w;

  

};

int main() {

// your code goes here

item data[5];

int tot_weight = 600;

  

// Enter the data

for(int i=0; i<5; i++)

cin>>data[i].v;

  

for(int i=0; i<5; i++)

cin>>data[i].w;

  

int res = 0;

  

for(int i=0; i<32; i++) // Max no. of subset = 32

{

int temp_weight = 0; int temp_val = 0;

for(int j =0; j<5; j++)

{

if(i & (1<<j)) // If ith bit is set

{

temp_weight += data[j].w;

temp_val += data[j].v;

}

}

if((temp_weight < tot_weight) && (temp_val > res)) // update the result

res = temp_val;

}

cout<<res;

return 0;

}

-----------------------------------Screenshot -------------------------

We are considering that we have to take full item (not its some part): (0/1 knapsack) Greedy approach to solve this is: Consider all subsets of the items and calculate the total weight and value of all subsets. We will consider only those subsets whose total weight is smaller than W. From all such subsets, pick the maximum value subset. Algorithm: Input: W is max weight possible item: It is an structure array . It has two parts: item.v = it's value: item.w = it's weight 1. Get the max no. of subsets possible max_no_of_subsets = pow (2, no_of_items) 2. Assign the result to zero result = 0 3. Loop for counter from 0 to max_no_of_subsets a) Assign the temporary variable to use them present_weight = 0: present_value = 0 (b) Loop for i = 0 to no_of_items\r\n

If any doubt ... please ask in comment section i wiil clear it