GeezerVison is showing github.com — java-coding-problems/InPlaceMergeSortedArray.java at main · GitH05/java-coding-problems

Expand file tree

InPlaceMergeSortedArray.java

Copy path

More file actions

Latest commit

History

49 lines (41 loc) · 1.46 KB

InPlaceMergeSortedArray.java

Copy path

File metadata and controls

49 lines (41 loc) · 1.46 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

import java.util.Arrays;

class InPlaceMergeSortedArray

{

// Function to in-place merge two sorted arrays X[] and Y[]

// invariant: `X[]` and `Y[]` are sorted at any point

public static void merge(int[] X, int[] Y)

{

int m = X.length;

int n = Y.length;

// Consider each element `X[i]` of array `X` and ignore the element if it is

// already in the correct order; otherwise, swap it with the next smaller

// element, which happens to be the first element of `Y`.

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

{

// compare the current element of `X[]` with the first element of `Y[]`

if (X[i] > Y[0])

{

// swap `X[i]` with `Y[0]`

int temp = X[i];

X[i] = Y[0];

Y[0] = temp;

int first = Y[0];

// move `Y[0]` to its correct position to InPlaceMergeSortedArraytain the sorted

// order of `Y[]`. Note: `Y[1…n-1]` is already sorted

int k;

for (k = 1; k < n && Y[k] < first; k++) {

Y[k - 1] = Y[k];

}

Y[k - 1] = first;

}

public static void main(String[] args)

{

int[] X = { 1, 4, 7, 8, 10 };

int[] Y = { 2, 3, 9 };

merge(X, Y);

System.out.println("X: " + Arrays.toString(X));

System.out.println("Y: " + Arrays.toString(Y));

}