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+## Dynamic Memory Allocation in C
+
+- In this article, we will discuss how memory can be allocated dynamically in the C programming language.
+
+### Introduction
+
+>  Memory that has been allocated at compilation time cannot be altered after execution. This will result in a problem with memory loss or inadequacy.
+>
+> -  The answer is to dynamically create memory, that is, according to user requirements as the programme is being run.
+>- There are two ways to allocate memory:
+>  > 1. static Memory Allocation
+>  > 2. Dynamic Memory Allocation
+
+The standard library functions used for dynamic memory management are:
+
+
+ - Malloc()
+ - Calloc()
+ - Realloc()
+ - Free()
+ ## Malloc()
+ - Using this function, a runtime byte-sized memory block can be allocated.
+ - It gives back a void pointer that points to the base address of the memory that was allocated.
+ - Unknown values will be present in the allotted RAM because it has not been initialised.
+
+ **Syntax:**
+```
+void *malloc (size in bytes);
+```
+## Calloc()
+ - This function is utilized to allocate continuous memory chunks during runtime.
+- This was created specifically for arrays.
+- It gives back a void pointer that points to the base address of the memory that was allocated.
+
+
+**Syntax:**
+```
+ void *calloc ( numbers of elements, size in bytes);
+```
+## Realloc()
+ - It can reduce (or) extend the allocated memory and reallocates previously allocated memory. 
+ - It then returns a void pointer that points to the base address of the newly allocated memory.
+ **Syntax:**
+```
+void *realloc (pointer, newsize);
+```
+## Free()
+ - With dynamic runtime allocation, it is our obligation to release the space when it is not needed for efficient memory consumption. 
+ - This function frees (or) dealslocates previously allocated memory space.
+  **Syntax:**
+```
+void *free (pointer);
+```
+
+
+**program to demonstrate  standard library functions used for dynamic memory management.**
+```
+#include<stdio.h>
+
+void main()
+
+{
+
+int *arr,i,j,n;
+
+clrscr();
+
+printf("enter the number of elements in array");
+
+scanf("%d",&n);
+
+arr=(int*) malloc(n*sizeof(int));  //dynamically allocating memory
+
+//code to read the elements of an array
+
+for(i=0;i<n;i++)
+
+{
+
+printf("enter %d elment",i+1);
+
+scanf("%d",&arr[i]);
+
+}
+
+//code to display elements of array
+
+printf("elements in array are");
+
+for(i=0;i<n;i++)
+
+printf(" \t %d",arr[i]);
+
+//code to increase the size of an array by  using realloc function
+
+arr=(int*)realloc(arr, n+2);
+
+arr[n]=9;
+
+arr[n+1]=10;
+
+printf("element of an array after reallocating memory");
+
+for(i=0;i<=n+1;i++)
+
+printf("\t %d",arr[i]);
+
+free(arr);
+
+getch();
+
+return;
+
+}
+```
+**Output:**
+
+enter the number of elements in array 3
+
+0  1  2
+
+enter 1 element 10
+
+enter 2 element 20
+
+enter 3 element 30
+
+elements in array are
+
+10  20  30
+
+element of an array after reallocating memory
+
+10  20  30  9  10