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How to declare a Global variable inside any function in 'C'?

I want to declare a global variable inside a main() function...

Below is what I want the program to act like

#include<stdio.h>
int a[6];
int main()
{
  int n;
  scanf("%d",&n);
}

I want to create an array of user given size (here n-size) and I want to access that array globally. So instead of creating array of size '6' outside the main() function, I want to create array of 'n' size globally instead of passing array whenever function is called...

Solution

  • You may want to use an array allocated into the heap by using malloc

    #include<stdio.h>
int *a;
int main()
{
  int n;
  scanf("%d", &n);
  a = malloc(sizeof(*a) * n);
  if(a == NULL) {
      // malloc error
  }

  // use your array here

  free(a); // at the end of the program make sure to release the memory allocated before
}