Realloc stand for Reallocation. At the time of memory allocation using calloc() or malloc(), it may be possible memory is excess or insufficient. So for that reason we need to reallocate memory at the run time. realloc() is used to dynamically reallocate those memory without losing the data.
Calloc stands for Contiguous Allocation. To allocate memory dynamically we also use the function which is called as calloc() function. calloc() function on success returns the base address of the array and every memory location will be initialized to 0. Whereas in malloc() it was initialized by a garbage value.
In case of static memory allocation there are some drawbacks like: wastage of memory, less flexibility, permanent allocation of variables etc. To overcome these situations the concept of Dynamic Memory Allocation has been introduced. In dynamic memory allocation the memories can be allocated dynamically at run time. There 4 library functions that are described under <stdlib.h>
Suppose we have an array of length 5 named a shown below Now during the length of the array (5) is fixed here. But what if we need to change the size of the array as per circumstances? It won’t be possible right? Here comes the idea of dynamic memory allocation where we can change
Dynamic Memory Allocation in C – malloc(), calloc(), realloc() and free() Read More »
%p is a format specifier in C programming language used to print the pointer type data. It prints the memory address of the variable in hexadecimal form.
Difference between %u and %p format specifiers in C Read More »
%p is a format specifier in C programming language. It is used to print the pointer type data. It prints the memory address of the variable pointed by the pointer in hexadecimal form. In 64 bit systems the pointers are of 8 bytes. So, the full hexadecimal representation is: 0000000000000055. Let’s take an example Example
In computer programming dereferencing operator also known as indirection operator. It is used to represent a pointer. This dereferencing operator is denoted by an asterisk ” * “. Pointer variable stores the address of the variable it is pointing to. When a dereferencing operator is used then it returns the value of the variable it is pointing to.
Function pointer is used to store the address of a function, we can call the function later through this function pointer. This is a useful process because for any particular work like drawing a line we have to write a huge code. Instead of that we can call a function through function pointer. Syntax: Example:
Pointer to an array points to the 0th element of the array instead of pointing to the individual elements it point to the whole array. In case of pointer to an array we are creating a pointer variable defining the number of integer that is basically used to group or is generally used to mention the number of elements per row of an a array.
What is String?The string is a character array that ends with a null character denoted by ‘\0’. Now, in this program, we have to reverse a string in c programming.Suppose the Input is: codewindowThen the Output will be: wodniwedoc We have definitely different approaches to code this program. Using in-built function strrev() Without using in-built
