Given two arrays A and B of size N and an integer K, the task is to find the maximum possible sum of array A by swapping at most K elements with array B.
Examples:
Input: A[] = {2, 3, 4}, B[] = {6, 8, 5}, K = 1
Output: 15
Explanation: Swap A[0] and B[1]. Hence sum = 8 + 3 + 4 = 15.Input: A[] = {9, 7}, B[] = {5, 1}, K = 2
Output: 16
Explanation: Since all the elements of array A are greater than the elements of array B, no swaps are required.
Maximize Array sum by swapping at most K elements with another array using Sorting
The idea is to replace all the smallest elements present in A with the largest elements of B, till the value of A[i] < B[i] and K swaps are not complete.
Follow the steps mentioned below to implement the idea:
- Sort the array A and B in non-decreasing order.
- Traverse array A from the beginning and array B from the end, so that we can swap the minimum element of array A with the maximum element of array B.
- If the element of array A is smaller than that of array B, swap them. Otherwise, break the loop.
- Do this for at most K elements, and break the loop after that.
- Find the sum of the resultant array A.
Below is the implementation of the above approach:
// C++ implementation to find maximum // sum of array A by swapping // at most K elements with array B #include <bits/stdc++.h> using namespace std;
// Function to find the maximum sum void maximumSum( int a[], int b[],
int k, int n)
{ int i, j;
sort(a, a + n);
sort(b, b + n);
// If element of array a is
// smaller than that of
// array b, swap them.
for (i = 0, j = n - 1; i < k;
i++, j--) {
if (a[i] < b[j])
swap(a[i], b[j]);
else
break ;
}
// Find sum of resultant array
int sum = 0;
for (i = 0; i < n; i++)
sum += a[i];
cout << sum << endl;
} int main()
{ int K = 1;
int A[] = { 2, 3, 4 };
int B[] = { 6, 8, 5 };
int N = sizeof (A) / sizeof (A[0]);
maximumSum(A, B, K, N);
return 0;
} |
// Java implementation to find maximum // sum of array A by swapping // at most K elements with array B import java.util.*;
class GFG{
// Function to find the maximum sum static void maximumSum( int a[], int b[],
int k, int n)
{ int i, j;
Arrays.sort(a);
Arrays.sort(b);
// If element of array a is
// smaller than that of
// array b, swap them.
for (i = 0 , j = n - 1 ; i < k; i++, j--)
{
if (a[i] < b[j])
{
int temp = a[i];
a[i] = b[j];
b[j] = temp;
}
else
break ;
}
// Find sum of resultant array
int sum = 0 ;
for (i = 0 ; i < n; i++)
sum += a[i];
System.out.print(sum + "\n" );
} // Driver Code public static void main(String[] args)
{ int K = 1 ;
int A[] = { 2 , 3 , 4 };
int B[] = { 6 , 8 , 5 };
int N = A.length;
maximumSum(A, B, K, N);
} } // This code is contributed by sapnasingh4991 |
# Python3 implementation to find maximum # sum of array A by swapping # at most K elements with array B # Function to find the maximum sum def maximumSum(a, b, k, n):
a.sort()
b.sort()
# If element of array a is
# smaller than that of
# array b, swap them.
i = 0
j = n - 1
while i < k:
if (a[i] < b[j]):
a[i], b[j] = b[j], a[i]
else :
break
i + = 1
j - = 1
# Find sum of resultant array
sum = 0
for i in range (n):
sum + = a[i]
print ( sum )
# Driver code if __name__ = = "__main__" :
K = 1
A = [ 2 , 3 , 4 ]
B = [ 6 , 8 , 5 ]
N = len (A)
maximumSum(A, B, K, N)
# This code is contributed by chitranayal |
// C# implementation to find maximum // sum of array A by swapping // at most K elements with array B using System;
class GFG{
// Function to find the maximum sum static void maximumSum( int []a,
int []b,
int k, int n)
{ int i, j;
Array.Sort(a);
Array.Sort(b);
// If element of array a is
// smaller than that of
// array b, swap them.
for (i = 0, j = n - 1; i < k; i++, j--)
{
if (a[i] < b[j])
{
int temp = a[i];
a[i] = b[j];
b[j] = temp;
}
else
break ;
}
// Find sum of resultant array
int sum = 0;
for (i = 0; i < n; i++)
sum += a[i];
Console.Write(sum + "\n" );
} // Driver Code public static void Main()
{ int K = 1;
int []A = { 2, 3, 4 };
int []B = { 6, 8, 5 };
int N = A.Length;
maximumSum(A, B, K, N);
} } // This code is contributed by Code_Mech |
<script> // JavaScript implementation to find maximum // sum of array A by swapping // at most K elements with array B // Function to find the maximum sum function maximumSum(a, b, k, n)
{ let i, j;
a.sort();
b.sort();
// If element of array a is
// smaller than that of
// array b, swap them.
for (i = 0, j = n - 1; i < k;
i++, j--) {
if (a[i] < b[j])
{
let temp = a[i];
a[i] = b[j];
b[j] = temp;
}
else
break ;
}
// Find sum of resultant array
let sum = 0;
for (i = 0; i < n; i++)
sum += a[i];
document.write(sum);
} let K = 1;
let A = [2, 3, 4 ];
let B = [ 6, 8, 5 ];
let N = A.length;
maximumSum(A, B, K, N);
// This code is contributed by vaibhavrabadiya117. </script> |
15
Time Complexity: O(N*log(N))
Auxiliary Space: O(1)