Segmentation fault when using different functions

Question

I'm trying to separate my code more neatly by using functions. An issue I've been having is passing variables through different functions. If I leave all my code in my working function it will run no problem. It's when I create another function and pass variables to that function, that's when I get the issues.

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

int main(void)
{    
    workings();
    output();
}

void workings()
{   
    int x;
    int i;

    double total = 0;
    double squareRoot;
    double overall;

    scanf("%d", &x);

    int* array = malloc(x * sizeof(int));

    if (!array) {
        printf("There isn't enough memory \n");
        return;
    }

    int j = 0;

    while (j < x) {   
        scanf("%d", &array[j]);
        total += array[j] * array[j];
        j++;
    }

    squareRoot = sqrt(total);
}

void output(int x, double overall, double squareRoot, int* array)
{
    int k = 0;

    while (k < x) {
        overall = array[k] / squareRoot;
        printf("%.3f ", overall);
        k++;
    }
}

Answer 1

You must pass arguments to functions which require them.

Try this:

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

void workings(int *x_out, double *squareRoot_out, int** array_out);
void output(int x, double squareRoot, int* array);

int main(void)
{
    int x;
    double squareRoot;
    int* array;

    workings(&x, &squareRoot, &array);
    output(x, squareRoot, array);
}

void workings(int *x_out, double *squareRoot_out, int** array_out)
{

    int x;

    double total = 0;
    double squareRoot;

    scanf("%d", &x);

    int* array = malloc(x * sizeof(int));

    if (!array) {
        printf("There isn't enough memory \n");
        return;
    }

    int j = 0;

    while (j < x) {

        scanf("%d", &array[j]);

        total += array[j] * array[j];
        j++;
    }

    squareRoot = sqrt(total);

    /* pass data for later use to callee */
    *x_out = x;
    *squareRoot_out = squareRoot;
    *array_out = array;
}
void output(int x, double squareRoot, int* array)
{
    double overall;
    int k = 0;

    while (k < x) {

        overall = array[k] / squareRoot;
        printf("%.3f ", overall);

        k++;
    }
}

Changes I made are:

• Add prorotype declaretions of functions to be used before main() (where the functions are used).
  This is for safety: compilers cannot check arguments before knowing declaretions nor definitions of functions.
• Add arguments to workings() in order to export data used in the function.
• Use the arguments to export data.
• Remove variables overall and i in workings() because they weren't used.
• Remove overall parameter from output() function and declare it as local variable because the input is not used.
• Modify main() function to allocate memory for passing data and pass data between functions.