Merge_2_array.cpp

#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define sf scanf
#define pf printf
long long int binarySearch(long long int arr[],long long  int l, long long int r, long long int x)
{
  while (l <= r)
  {
    long long int m = l + (r-l)/2;

    if (arr[m] == x) return m;  // Check if x is present at mid

    if (arr[m] < x) l = m + 1; // If x greater, ignore left half

    else r = m - 1; // If x is smaller, ignore left half
  }
  return -1; // if we reach here, then element was not present
}
void merge(long long int arr[], long long int l, long long int m, long long int r)
{
    long long int i, j, k;
    long long int n1 = m - l + 1;
    long long int n2 =  r - m;

    /* create temp arrays */
   long long  int L[n1], R[n2];

    /* Copy data to temp arrays L[] and R[] */
    for(i = 0; i < n1; i++)
        L[i] = arr[l + i];
    for(j = 0; j < n2; j++)
        R[j] = arr[m + 1+ j];

    /* Merge the temp arrays back into arr[l..r]*/
    i = 0;
    j = 0;
    k = l;
    while (i < n1 && j < n2)
    {
        if (L[i] <= R[j])
        {
            arr[k] = L[i];
            i++;
        }
        else
        {
            arr[k] = R[j];
            j++;
        }
        k++;
    }

    /* Copy the remaining elements of L[], if there are any */
    while (i < n1)
    {
        arr[k] = L[i];
        i++;
        k++;
    }

    /* Copy the remaining elements of R[], if there are any */
    while (j < n2)
    {
        arr[k] = R[j];
        j++;
        k++;
    }
}

/* l is for left index and r is right index of the sub-array
  of arr to be sorted */
void mergeSort(long long int arr[], long long int l, long long int r)
{
    if (l < r)
    {
        long long  int m = l+(r-l)/2;//Same as (l+r)/2, but avoids overflow for large l and h
        mergeSort(arr, l, m);
	    mergeSort(arr, m+1, r);
        merge(arr, l, m, r);
    }
}
void printArray(long long int A[], long long int size)
{
   long long  int i;
    for (i=0; i < size; i++)
        printf("%lld ", A[i]);
    printf("\n");
}
 
void merge(int ar1[], int ar2[], int m, int n)
{
    for (int i=n-1; i>=0; i--)
    {
        int j, last = ar1[m-1];
        for (j=m-1; j >= 0 && ar1[j] > ar2[i]; j--)
            ar1[j+1] = ar1[j];

        if (j != m-1)
        {
            ar1[j+1] = ar2[i];
            ar2[i] = last;
        }
    }
}
int main(void)
{
	int m,n;
	scanf("%d%d",&m,&n);
	int ar1[m],ar2[n];
	for (int i=0; i<m; i++)
	scanf("%d",&ar1[i]);
	for (int i=0; i<n; i++)
	scanf("%d",&ar2[i]);
    merge(ar1, ar2, m, n);
    cout << "After Merging \nFirst Array: ";
    for (int i=0; i<m; i++)
        cout << ar1[i] << " ";
    cout << "\nSecond Array: ";
    for (int i=0; i<n; i++)
        cout << ar2[i] << " ";
   return 0;
}