Write a C Program to Copy One to Another String using Recursion

Recursion : :

• Recursion is the process of repeating items in a self-similar way. In programming languages, if a program allows you to call a function inside the same function, then it is called a recursive call of the function.

• The C programming language supports recursion, i.e., a function to call itself. But while using recursion, programmers need to be careful to define an exit condition from the function, otherwise it will go into an infinite loop.

• Recursive functions are very useful to solve many mathematical problems, such as calculating the factorial of a number, generating Fibonacci series, etc.

Problem : :

This C Program uses recursive function & copies a string entered by user from one character array to another character array.

Here is the source code of the C program to copy string using recursion. The C Program is successfully compiled and run on a Windows system. The program output is also shown below.

SOURCE CODE : :

/*  C Program to Copy One to Another String using Recursion  */


#include <stdio.h>
 
void copy(char [], char [], int);
 
int main()
{
    char str1[20], str2[20];
 
    printf("Enter string to copy: ");
    scanf("%s", str1);
    copy(str1, str2, 0);
    printf("Copying success.\n");
    printf("The first string is: %s\n", str1);
    printf("The second string is: %s\n", str2);
    return 0;
}
 
void copy(char str1[], char str2[], int index)
{
    str2[index] = str1[index];
    if (str1[index] == '\0')
        return;
    copy(str1, str2, index + 1);
}

Output : :

*************** OUTPUT ******************


Enter string to copy: CodezClub

Copying success.

The first string is: CodezClub

The second string is: CodezClub