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++
// 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
// 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
# 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#
// 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 |
Javascript
<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)
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