Merge an array of size n into another array of size m+n
There are two sorted arrays. First one is of size m+n containing only m elements. Another one is of size n and contains n elements. Merge these two arrays into the first array of size m+n such that the output is sorted.
Input: array with m+n elements (mPlusN[]).
NA => Value is not filled/available in array mPlusN[]. There should be n such array blocks.
Input: array with n elements (N[]).
Output: N[] merged into mPlusN[] (Modified mPlusN[])
Algorithm:
Let first array be mPlusN[] and other array be N[] 1) Move m elements of mPlusN[] to end. 2) Start from nth element of mPlusN[] and 0th element of N[] and merge them into mPlusN[].
Below is the implementation of the above algorithm :
C++
// C++ program to Merge an array of // size n into another array of size m + n #include <bits/stdc++.h> using namespace std; /* Assuming -1 is filled for the places where element is not available */#define NA -1 /* Function to move m elements at the end of array mPlusN[] */void moveToEnd(int mPlusN[], int size) { int j = size - 1; for (int i = size - 1; i >= 0; i--) if (mPlusN[i] != NA) { mPlusN[j] = mPlusN[i]; j--; } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/void merge(int mPlusN[], int N[], int m, int n) { int i = n; /* Current index of i/p part of mPlusN[]*/ int j = 0; /* Current index of N[]*/ int k = 0; /* Current index of output mPlusN[]*/ while (k < (m + n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if ((j == n)||(i < (m + n) && mPlusN[i] <= N[j])) { mPlusN[k] = mPlusN[i]; k++; i++; } else // Otherwise take element from N[] { mPlusN[k] = N[j]; k++; j++; } } } /* Utility that prints out an array on a line */void printArray(int arr[], int size) { for (int i = 0; i < size; i++) cout << arr[i] << " "; cout << endl; } /* Driver code */int main() { /* Initialize arrays */ int mPlusN[] = {2, 8, NA, NA, NA, 13, NA, 15, 20}; int N[] = {5, 7, 9, 25}; int n = sizeof(N) / sizeof(N[0]); int m = sizeof(mPlusN) / sizeof(mPlusN[0]) - n; /*Move the m elements at the end of mPlusN*/ moveToEnd(mPlusN, m + n); /*Merge N[] into mPlusN[] */ merge(mPlusN, N, m, n); /* Print the resultant mPlusN */ printArray(mPlusN, m+n); return 0; } |
C
// C program to Merge an array of // size n into another array of size m + n #include <stdio.h> /* Assuming -1 is filled for the places where element is not available */#define NA -1 /* Function to move m elements at the end of array mPlusN[] */void moveToEnd(int mPlusN[], int size) { int i = 0, j = size - 1; for (i = size - 1; i >= 0; i--) if (mPlusN[i] != NA) { mPlusN[j] = mPlusN[i]; j--; } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/void merge(int mPlusN[], int N[], int m, int n) { int i = n; /* Current index of i/p part of mPlusN[]*/ int j = 0; /* Current index of N[]*/ int k = 0; /* Current index of output mPlusN[]*/ while (k < (m + n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if ((j == n)|| (i < (m + n) && mPlusN[i] <= N[j])) { mPlusN[k] = mPlusN[i]; k++; i++; } else // Otherwise take element from N[] { mPlusN[k] = N[j]; k++; j++; } } } /* Utility that prints out an array on a line */void printArray(int arr[], int size) { int i; for (i = 0; i < size; i++) printf("%d ", arr[i]); printf("\n"); } /* Driver code */int main() { /* Initialize arrays */ int mPlusN[] = { 2, 8, NA, NA, NA, 13, NA, 15, 20 }; int N[] = { 5, 7, 9, 25 }; int n = sizeof(N) / sizeof(N[0]); int m = sizeof(mPlusN) / sizeof(mPlusN[0]) - n; /*Move the m elements at the end of mPlusN*/ moveToEnd(mPlusN, m + n); /*Merge N[] into mPlusN[] */ merge(mPlusN, N, m, n); /* Print the resultant mPlusN */ printArray(mPlusN, m + n); return 0; } |
Java
// Java program to Merge an array of // size n into another array of size m + n class MergeArrays { /* Function to move m elements at the end of array * mPlusN[] */ void moveToEnd(int mPlusN[], int size) { int i, j = size - 1; for (i = size - 1; i >= 0; i--) { if (mPlusN[i] != -1) { mPlusN[j] = mPlusN[i]; j--; } } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/ void merge(int mPlusN[], int N[], int m, int n) { int i = n; /* Current index of i/p part of mPlusN[]*/ int j = 0; /* Current index of N[]*/ int k = 0; /* Current index of output mPlusN[]*/ while (k < (m + n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if ((i < (m + n) && mPlusN[i] <= N[j]) || (j == n)) { mPlusN[k] = mPlusN[i]; k++; i++; } else // Otherwise take element from N[] { mPlusN[k] = N[j]; k++; j++; } } } /* Utility that prints out an array on a line */ void printArray(int arr[], int size) { int i; for (i = 0; i < size; i++) System.out.print(arr[i] + " "); System.out.println(""); } // Driver Code public static void main(String[] args) { MergeArrays mergearray = new MergeArrays(); /* Initialize arrays */ int mPlusN[] = { 2, 8, -1, -1, -1, 13, -1, 15, 20 }; int N[] = { 5, 7, 9, 25 }; int n = N.length; int m = mPlusN.length - n; /*Move the m elements at the end of mPlusN*/ mergearray.moveToEnd(mPlusN, m + n); /*Merge N[] into mPlusN[] */ mergearray.merge(mPlusN, N, m, n); /* Print the resultant mPlusN */ mergearray.printArray(mPlusN, m + n); } } // This code has been contributed by Mayank Jaiswal |
Python3
# Python program to Merge an array of # size n into another array of size m + n NA = -1 # Function to move m elements # at the end of array mPlusN[] def moveToEnd(mPlusN, size): i = 0 j = size - 1 for i in range(size-1, -1, -1): if (mPlusN[i] != NA): mPlusN[j] = mPlusN[i] j -= 1 # Merges array N[] # of size n into array mPlusN[] # of size m+n def merge(mPlusN, N, m, n): i = n # Current index of i/p part of mPlusN[] j = 0 # Current index of N[] k = 0 # Current index of output mPlusN[] while (k < (m+n)): # Take an element from mPlusN[] if # a) value of the picked # element is smaller and we have # not reached end of it # b) We have reached end of N[] */ if ((j == n) or (i < (m+n) and mPlusN[i] <= N[j])): mPlusN[k] = mPlusN[i] k += 1 i += 1 else: # Otherwise take element from N[] mPlusN[k] = N[j] k += 1 j += 1 # Utility that prints # out an array on a line def printArray(arr, size): for i in range(size): print(arr[i], " ", end="") print() # Driver function to # test above functions # Initialize arrays mPlusN = [2, 8, NA, NA, NA, 13, NA, 15, 20] N = [5, 7, 9, 25] n = len(N) m = len(mPlusN) - n # Move the m elements # at the end of mPlusN moveToEnd(mPlusN, m+n) # Merge N[] into mPlusN[] merge(mPlusN, N, m, n) # Print the resultant mPlusN printArray(mPlusN, m+n) # This code is contributed # by Anant Agarwal. |
C#
// C# program to Merge an array of // size n into another array of size m + n using System; class GFG { /* Function to move m elements at the end of array mPlusN[] */ public virtual void moveToEnd(int[] mPlusN, int size) { int i, j = size - 1; for (i = size - 1; i >= 0; i--) { if (mPlusN[i] != -1) { mPlusN[j] = mPlusN[i]; j--; } } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/ public virtual void merge(int[] mPlusN, int[] N, int m, int n) { int i = n; /* Current index of i/p part of mPlusN[]*/ int j = 0; /* Current index of N[]*/ int k = 0; /* Current index of output mPlusN[]*/ while (k < (m + n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if ((j == n)(i < (m + n) && mPlusN[i] <= N[j])) { mPlusN[k] = mPlusN[i]; k++; i++; } else // Otherwise take element from N[] { mPlusN[k] = N[j]; k++; j++; } } } /* Utility that prints out an array on a line */ public virtual void printArray(int[] arr, int size) { int i; for (i = 0; i < size; i++) { Console.Write(arr[i] + " "); } Console.WriteLine(""); } // Driver Code public static void Main(string[] args) { GFG mergearray = new GFG(); /* Initialize arrays */ int[] mPlusN = new int[] { 2, 8, -1, -1, -1, 13, -1, 15, 20 }; int[] N = new int[] { 5, 7, 9, 25 }; int n = N.Length; int m = mPlusN.Length - n; /*Move the m elements at the end of mPlusN*/ mergearray.moveToEnd(mPlusN, m + n); /*Merge N[] into mPlusN[] */ mergearray.merge(mPlusN, N, m, n); /* Print the resultant mPlusN */ mergearray.printArray(mPlusN, m + n); } } // This code is contributed by Shrikant13 |
PHP
<?php // PHP program to Merge an array // of size n into another array // of size m + n /* Assuming -1 is filled for the places where element is not available */$NA = -1; /* Function to move m elements at the end of array mPlusN[] */function moveToEnd(&$mPlusN, $size) { global $NA; $j = $size - 1; for ($i = $size - 1; $i >= 0; $i--) if ($mPlusN[$i] != $NA) { $mPlusN[$j] = $mPlusN[$i]; $j--; } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/function merge(&$mPlusN, &$N, $m, $n) { $i = $n; /* Current index of i/p part of mPlusN[]*/ $j = 0; /* Current index of N[]*/ $k = 0; /* Current index of output mPlusN[]*/ while ($k < ($m + $n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if (($j == $n) || ($i < ($m + $n) && $mPlusN[$i] <= $N[$j])) { $mPlusN[$k] = $mPlusN[$i]; $k++; $i++; } else // Otherwise take element from N[] { $mPlusN[$k] = $N[$j]; $k++; $j++; } } } /* Utility that prints out an array on a line */function printArray(&$arr, $size) { for ($i = 0; $i < $size; $i++) echo $arr[$i] . " "; echo "\n"; } // Driver Code /* Initialize arrays */$mPlusN = array(2, 8, $NA, $NA, $NA, 13, $NA, 15, 20); $N = array(5, 7, 9, 25); $n = sizeof($N); $m = sizeof($mPlusN) - $n; /* Move the m elements at the end of mPlusN*/moveToEnd($mPlusN, $m + $n); /* Merge N[] into mPlusN[] */merge($mPlusN, $N, $m, $n); /* Print the resultant mPlusN */printArray($mPlusN, $m+$n); // This code is contributed // by ChitraNayal ?> |
Javascript
<script> // Javascript program to Merge an array of // size n into another array of size m + n /* Function to move m elements at the end of array * mPlusN[] */ function moveToEnd(mPlusN,size) { let i = 0; let j = size - 1; for (i = size - 1; i >= 0; i--) { if (mPlusN[i] != -1) { mPlusN[j] = mPlusN[i]; j--; } } } /* Merges array N[] of size n into array mPlusN[] of size m+n*/ function merge(mPlusN, N, m, n) { let i = n; /* Current index of i/p part of mPlusN[]*/ let j = 0; /* Current index of N[]*/ let k = 0; /* Current index of output mPlusN[]*/ while (k < (m + n)) { /* Take an element from mPlusN[] if a) value of the picked element is smaller and we have not reached end of it b) We have reached end of N[] */ if ((i < (m + n) && mPlusN[i] <= N[j]) || (j == n)) { mPlusN[k] = mPlusN[i]; k++; i++; } else // Otherwise take element from N[] { mPlusN[k] = N[j]; k++; j++; } } } /* Utility that prints out an array on a line */ function printArray(arr,size) { let i = 0; for (i = 0; i < size; i++) { document.write(arr[i] + " "); } document.write("\n"); } // Driver Code /* Initialize arrays */ let mPlusN = [2, 8, -1, -1, -1, 13, -1, 15, 20]; let N = [ 5, 7, 9, 25] let n = N.length; let m = mPlusN.length - n; /*Move the m elements at the end of mPlusN*/ moveToEnd(mPlusN, m + n); /*Merge N[] into mPlusN[] */ merge(mPlusN, N, m, n); /* Print the resultant mPlusN */ printArray(mPlusN, m + n); // This code is contributed by avanitrachhadiya2155 </script> |
Output
2 5 7 8 9 13 15 20 25
Time Complexity: O(m+n)
Auxiliary Space: O(1)
Please write a comment if you find any bug in the above program or a better way to solve the same problem.
Feeling lost in the world of random DSA topics, wasting time without progress? It’s time for a change! Join our DSA course, where we’ll guide you on an exciting journey to master DSA efficiently and on schedule.
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 zambiatek!
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 zambiatek!
