Write the steps for mail merging …

<pre> #include<iostream> #include<conio.h> using namespace std; void mergesort(int *,int,int); void merge(int *,int,int,int); int a[20],i,n,b[20];   main() { cout <<"\n enter no of elements"; cin >> n; cout <<"enter the elements"; for(i=0;i<n;i++) cin >> a[i]; mergesort(a,0,n-1); cout <<" numbers after sort"; for(i=0;i<n;i++) cout << a[i] << " "; getch(); }   void mergesort(int a[],int i,int j) { int mid; if(i<j) { mid=(i+j)/2; mergesort(a,i,mid); mergesort(a,mid+1,j); merge(a,i,mid,j); } } void merge(int a[],int low,int mid ,int high) { int h,i,j,k; h=low; i=low; j=mid+1; while(h<=mid && j<=high) { if(a[h]<=a[j]) b[i]=a[h++]; else b[i]=a[j++]; i++; }   if( h > mid) for(k=j;k<=high;k++) b[i++]=a[k]; else for(k=h;k<=mid;k++) b[i++]=a[k];   cout <<"\n"; for(k=low;k<=high;k++) { a[k]=b[k]; cout << a[k] <<" "; }   }</pre>

 

Source: <a href="http://electrofriends.com/source-codes/software-programs/cpp-programs/cpp-basic-programs/c-programs-for-sorting-a-given-numbers-in-ascending-order-using-merge-sort/">Electrofriends</a>