merge sorted arrays.cpp

// C++ program to merge two sorted arrays/ 
#include<iostream> 
using namespace std; 

// Merge arr1[0..n1-1] and arr2[0..n2-1] into 
// arr3[0..n1+n2-1] 
void mergeArrays(int arr1[], int arr2[], int n1, 
							int n2, int arr3[]) 
{ 
	int i = 0, j = 0, k = 0; 

	// Traverse both array 
	while (i<n1 && j <n2) 
	{ 
		// Check if current element of first 
		// array is smaller than current element 
		// of second array. If yes, store first 
		// array element and increment first array 
		// index. Otherwise do same with second array 
		if (arr1[i] < arr2[j]) 
			arr3[k++] = arr1[i++]; 
		else
			arr3[k++] = arr2[j++]; 
	} 

	// Store remaining elements of first array 
	while (i < n1) 
		arr3[k++] = arr1[i++]; 

	// Store remaining elements of second array 
	while (j < n2) 
		arr3[k++] = arr2[j++]; 
} 

// Driver code 
int main() 
{ 
	int arr1[] = {1, 3, 5, 7}; 
	int n1 = sizeof(arr1) / sizeof(arr1[0]); 

	int arr2[] = {2, 4, 6, 8}; 
	int n2 = sizeof(arr2) / sizeof(arr2[0]); 

	int arr3[n1+n2]; 
	mergeArrays(arr1, arr2, n1, n2, arr3); 

	cout << "Array after merging" <<endl; 
	for (int i=0; i < n1+n2; i++) 
		cout << arr3[i] << " "; 

	return 0; 
}