Memory allocation at run time

Can someone clarify what's memory allocation at run time ?

When I need to write a program I write it on editor and save it. when i compile/run program. compiler allocate memory. if there is error in code compiler show error. if there is no error then compiler show result

Code:

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#include<stdio.h>#include<stdlib.h>
 
int main ()
{
  int *x = malloc(sizeof(*x)); // allocate dynamic memory for x
  *x = 1; 
  printf( "x = %d\n", *x);


  return 0;
 
}

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In a program dynamic memory will allocate for pointer when i compile and run the code

What's term " Memory allocation at run time " in code development?

Well you're doing dynamic allocation (which is also the definition of "at runtime") when you call malloc / calloc / realloc / free.

Your code should be

Code:

---

#include<stdio.h>
#include<stdlib.h>
 
int main ()
{
  int *x = malloc(sizeof(*x)); // allocate dynamic memory for x
  if ( x != NULL ) { // always check, it might fail
    *x = 1; 
    printf( "x = %d\n", *x);
    free(x);  // always free when you're done.
  }

  return 0; 
}

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