Question

Hey im trying to refresh my mind with a bit of recursion.
I want to add all numbers from ‘start’ to ‘end’ inclusive.

I.e if start was 1, and end was 5. Then the answer would be 1+2+3+4+5 = 15

So far I’ve got this

int calc(int start, int end){
    if(start > end)
        return total;
    else{
        total = total + start;  
    return sum1(start++, end);
    }
} 

Its not working (i get seg fault). What am i doing wrong?

EDIT: Sorry i am using the same variables in my actual code, when i wrote this i ended up reffering to them as start/end and forgot to change all the code.

Answer 1

What are from and to variables inside your function? Maybe you use some globals instead of using start and end and that’s why you have the problem? Also why are you using sum1 inside the calc function instead of calc?

Try this instead:

int calc(int start, int end){
    if(start > end)
        return 0;
    else
        return start + calc(start + 1, end);
}