**Memory allocation** (malloc), is an in-built function in C. This function is used to assign a specified amount of memory for an array to be created. It also returns a pointer to the space allocated in memory using this function. 

# The need for malloc

In the world of programming where every space counts, there are numerous times when we only want an array to have a specific amount of space at run time. That is, we want to create an array occupying a particular amount of space, dynamically. We do this using *malloc*.

# Syntax

We know what malloc returns and we know what it requires as an input, but how does the syntax of the function work. The illustration below shows that:

>**Note:** malloc will return `NULL` if the memory specified is not available and hence, the allocation has failed


# Examples

Now that we know how malloc is used and why it is needed, let's look at a few code examples to see how it is used in the code.

#include<stdio.h>
#include <stdlib.h> 
int main() {

    int* ptr1;
    // We want ptr1 to store the space of 3 integers
    ptr1 = (int*) malloc (3 * sizeof(int));

    if(ptr1==NULL){
      printf("Memory not allocated. \n");
    }
    else{printf("Memory allocated successfully. \n");
    // This statement shows where memory is allocated
    printf("The address of the pointer is:%u\n ", ptr1);
    
    // Here we assign values to the ptr1 created
    for(int i=0;i<3;i++){
      ptr1[i] = i;
    }
    // Printing the vlaues of ptr1 to show memory allocation is done
    for(int i=0;i<3;i++){
      printf("%d\n", ptr1[i]);
    }

    }
    
}

How to use "malloc" in C

Memory allocation in C assigns specified memory for arrays at runtime using `malloc`, returning a memory pointer.