nChoosek

[sebajun]

This is a program that prompts the user to enter a "n" value and a "k" value, and return how many different ways one can choose a value k from a distinct group n.

My code crashes and I don't see why.

Any help with a solution would be great thanks.

#include <stdio.h>
#include <math.h>
#include <stdlib.h>

int n_choose_k(int n, int k);

int factorial(int m);

int main(int argc, char *argv[]){

    int input_n;

    int input_k;

    printf("Enter your 'n' & 'k' values:");

    scanf("%d\n", input_n);

    scanf("%d\n", input_k);

    printf("nCk = %d", n_choose_k(input_n, input_k));

    return 0;

}

int n_choose_k(int n, int k){

    int resnCk;

    resnCk = factorial(n)/(factorial((n-k))*(factorial(k)));

    return resnCk;
}




int factorial(int m){

    int result=m;

    int i;

    for(i=0;i<m;i++){

        result *= (result-1);

    }

    return result;

}

[cPlusN00b]

I think your problem is in lines 5 and 7.
First, that's not how you declare a function. Second, you don't need to there, those function are already defined. (lines 27 - 49)

Just erase lines 5 and 7, for reals, and see if it doesn't at least compile then.

[cPlusN00b]

If ya still have an issue I would move the main function to line 50, after the factorial function. It will still run first.

[Peter87]

There is nothing wrong with how the functions are declared.

You should pass pointers to scanf.

scanf("%d\n", &input_n);
scanf("%d\n", &input_k);

[sebajun]

Thank you both, all good now.