Function to copy string (Iterative and Recursive)

Given two strings, copy one string to other using recursion. We basically need to write our own recursive version of strcpy in C/C++

Examples:

Input : s1 = "hello"
        s2 = "geeksforgeeks"
Output : s2 = "hello"

Input :  s1 = "geeksforgeeks"
         s2 = ""
Output : s2 = "geeksforgeeks"

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Iterative :
Copy every character from s1 to s2 starting from index = 0 and in each call increase the index by 1 until s1 doesn’t reach to end;

C++

// Iterative CPP Program to copy one String   
// to another. 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to copy one string to other 
// assuming that other string has enough 
// space. 
void myCopy(char s1[], char s2[]) 
{ 
    int i = 0; 
    for (i=0; s1[i] != '\0'; i++) 
       s2[i] = s1[i]; 
    s2[i] = '\0'; 
} 
  
// Driver function 
int main() 
{ 
    char s1[100] = "GEEKSFORGEEKS"; 
    char s2[100] = ""; 
    myCopy(s1, s2); 
    cout << s2; 
    return 0; 
} 

Java

// Iterative Java Program to copy one String  
// to another. 
class GFG 
{ 
      
// Function to copy one string to other 
// assuming that other string has enough 
// space. 
static void myCopy(char s1[], char s2[]) 
{ 
    int i = 0; 
    for (i = 0; i < s1.length; i++) 
         s2[i] = s1[i]; 
} 
  
// Driver code 
public static void main(String[] args)  
{ 
    char s1[] = "GEEKSFORGEEKS".toCharArray(); 
    char s2[] = new char[s1.length]; 
    myCopy(s1, s2); 
    System.out.println(String.valueOf(s2)); 
} 
} 
  
// This code contributed by Rajput-Ji 

Python3

# Iterative Python Program to copy one String  
# to another. 
  
# Function to copy one string to other 
# assuming that other string has enough 
# space. 
def myCopy(s1, s2): 
  
    for i in range(len(s1)): 
        s2[i] = s1[i]; 
  
# Driver code 
s1 = "GEEKSFORGEEKS"; 
s2 = ['']*(len(s1)); 
myCopy(s1, s2); 
print(("".join(s2))); 
  
# This code contributed by PrinciRaj1992 

C#

// Iterative C# Program to copy one String  
// to another. 
using System;  
  
class GFG 
{ 
      
// Function to copy one string to other 
// assuming that other string has enough 
// space. 
static void myCopy(char []s1, char []s2) 
{ 
    int i = 0; 
    for (i = 0; i < s1.Length; i++) 
        s2[i] = s1[i]; 
} 
  
// Driver code 
public static void Main(String[] args)  
{ 
    char []s1 = "GEEKSFORGEEKS".ToCharArray(); 
    char []s2 = new char[s1.Length]; 
    myCopy(s1, s2); 
    Console.WriteLine(String.Join("", s2)); 
} 
} 
  
// This code is contributed by 29AjayKumar 

Output:

GEEKSFORGEEKS

Recursive :
Copy every character from s1 to s2 starting from index = 0 and in each call increase the index by 1 until s1 doesn’t reach to end;

C++

// CPP Program to copy one String to  
// another using Recursion 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to copy one string in to other 
// using recursion 
void myCopy(char s1[], char s2[], int index = 0) 
{ 
    // copying each character from s1 to s2 
    s2[index] = s1[index];  
  
    // if string reach to end then stop  
    if (s1[index] == '\0')   
        return; 
  
    // increase character index by one 
    myCopy(s1, s2, index + 1);  
} 
  
// Driver function 
int main() 
{ 
    char s1[100] = "GEEKSFORGEEKS"; 
    char s2[100] = ""; 
    myCopy(s1, s2); 
    cout << s2; 
    return 0; 
} 

Java

// Java Program to copy one String to  
// another using Recursion  
class GFG  
{ 
      
    // Function to copy one string in to other  
    // using recursion  
    static void myCopy(char s1[],  
                       char s2[], int index)  
    { 
        // copying each character from s1 to s2  
        s2[index] = s1[index]; 
  
        // if string reach to end then stop  
        if (index == s1.length - 1) 
        { 
            return; 
        } 
  
        // increase character index by one  
        myCopy(s1, s2, index + 1); 
    } 
  
    // Driver Code  
    public static void main(String[] args)  
    { 
        char s1[] = "GEEKSFORGEEKS".toCharArray(); 
        char s2[] = new char[s1.length]; 
        int index = 0; 
        myCopy(s1, s2, index); 
        System.out.println(String.valueOf(s2)); 
    } 
} 
  
// This code is contributed by PrinciRaj1992  

Python3

# Python3 Program to copy one String to  
# another using Recursion  
  
# Function to copy one string in to other  
# using recursion  
def myCopy(s1, s2, index): 
      
    # copying each character from s1 to s2  
    s2[index] = s1[index]; 
  
    # if string reach to end then stop  
    if (index == len(s1) - 1): 
        return; 
  
    # increase character index by one  
    myCopy(s1, s2, index + 1); 
  
# Driver Code  
if __name__ == '__main__': 
    s1 = "GEEKSFORGEEKS"; 
    s2 = [0] * (len(s1)); 
    index = 0; 
    myCopy(s1, s2, index); 
    print("".join(s2)); 
  
# This code is contributed by 29AjayKumar 

C#

// C# Program to copy one String to  
// another using Recursion  
using System; 
  
class GFG  
{ 
      
    // Function to copy one string in to other  
    // using recursion  
    static void myCopy(char []s1,  
                       char []s2, int index)  
    { 
        // copying each character from s1 to s2  
        s2[index] = s1[index]; 
  
        // if string reach to end then stop  
        if (index == s1.Length - 1) 
        { 
            return; 
        } 
  
        // increase character index by one  
        myCopy(s1, s2, index + 1); 
    } 
  
    // Driver Code  
    public static void Main(String[] args)  
    { 
        char []s1 = "GEEKSFORGEEKS".ToCharArray(); 
        char []s2 = new char[s1.Length]; 
        int index = 0; 
        myCopy(s1, s2, index); 
        Console.WriteLine(String.Join("", s2)); 
    } 
} 
  
// This code is contributed by Princi Singh 

Output:

GEEKSFORGEEKS

My Personal Notes

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

Java

Python3

C#

C++

Java

Python3

C#

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