C: Given two numbers a=20 b =30 write a method that return an int c=3020 without using arithmetic and string operations?

Question

It was asked today in interview but could not crack it, any help.

Answer 1

Its concat i.e. b followed by a. Just need to do some trick

#include <stdio.h>

#define myfunc(a,c) b##a

int main()
{
    int c;
    c = myfunc(20,30);
    printf("%d\n", c);
    return 0;
}

Answer 2

#include <stdio.h>

int main(void) {
    int a, b;
    scanf("%d%d",&a,&b);
    printf("%d",b);
    printf("%d",a);
    return 0;
}

output
3020

Answer 3

I think there is no other way except string concatenation and arithmetic operation for your problem.
I would give you simple arithmetic logic

int a=20;
int b=30;
int c=(b*100)+a;

if you tell your purpose i would give a better solution
thank you.

Comments

Question was saying no arithmetic operation :) so no + - * /