program 19: finding the GCD/HCF of 2 numbers

The need:

     This program was given to me as a lab assignment.

The code:

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//Finding HCF
#include<stdio.h>
main()
{
    printf("Enter two integers to get their hcf ..\n");
    long int i,j,k;
    scanf("%ld  %ld",&i,&j);
    ranu:
    k=i%j;
    if(k!=0)
    {i=j;
    j=k;
    goto ranu;}
    else
    printf("The hcf of given numbers is %ld\n\n\n",j);
}
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The approach:
     In this program I have used the same division method for finding GCD that you use when you calculate GCD with a paper pen(If you have ever used). In the same way in each run of loop I am making remainder the divisor and divisor the dividend if the remainder is not 0. If the remainder is found 0 then loop terminates and corresponding value of divisor is the GCD.
      In this program I used 'goto' because by that time I was not aware of  'for' loop. I think you are smart enough to rewrite this program using 'for' and 'while' loop if you have gone through program12, program13 and program14 of this blog so I am not going to put those programs in this blog.