MergeSort.cpp

/*
C++ program to merge two arrays into third array: Arrays are assumed to be sorted in ascending order.
You enter two short sorted arrays and combine them to get a large array.
*/

#include <iostream.h>
#include<conio.h> 
void merge(int [], int, int [], int, int []);
 
int main() {
  int a[100], b[100], m, n, c, sorted[200];
 
  cout<<"Input number of elements in first array\n";
  cin>>m;
 
  cout<<"Input Elelemts";
  for (c = 0; c < m; c++) {
    cin>>a[c];
  }
 
  cout<<"Input number of elements in second array\n";
  cin>>n;
 
  cout<<"Input Elelemts\n";
  for (c = 0; c < n; c++) {
    cin>>b[c];
  }
 
  merge(a, m, b, n, sorted);
 
  cout<<"Sorted array:\n";
 
  for (c = 0; c < m + n; c++) {
    cout<<endl<<sorted[c];
  }
 getch();
  return 0;
}
 
void merge(int a[], int m, int b[], int n, int sorted[]) {
  int i, j, k;
 
  j = k = 0;
 
  for (i = 0; i < m + n;) {
    if (j < m && k < n) {
      if (a[j] < b[k]) {
        sorted[i] = a[j];
        j++;
      }
      else {
        sorted[i] = b[k];
        k++;
      }
      i++;
    }
    else if (j == m) {
      for (; i < m + n;) {
        sorted[i] = b[k];
        k++;
        i++;
      }
    }
    else {
      for (; i < m + n;) {
        sorted[i] = a[j];
        j++;
        i++;
      }
    }
  }
}