TCS Coding Practice Question | Concatenate 2 Strings

Last Updated : 11 Jan, 2023

Given two Strings, the task is to concatenate the two Strings using Command Line Arguments.

Examples:

Input: str1 = "hello", str2 = "world"
Output: helloworld

Input: str1 = "Geeks", str2 = "World"
Output: GeeksWorld

Approach:

Since the Strings are entered as Command line Arguments, there is no need for a dedicated input line
Extract the input Strings from the command line argument
Concatenate the given strings using the respective methods.
Print or return the concatenated strings

Program:

C

// C program to concatenate the two Strings 
// using command line arguments 
  
#include <stdio.h> 
#include <stdlib.h> /* atoi */ 
#include <string.h> 
  
// Function to concatenate the Strings 
char* concat(char dest[], char src[]) 
{ 
  
    // Appends the entire string 
    // of src to dest 
    strcat(dest, src); 
  
    // Return the concatenated String 
    return dest; 
} 
  
// Driver code 
int main(int argc, char* argv[]) 
{ 
    // Check if the length of args array is 1 
    if (argc == 1) 
        printf("No command line arguments found.\n"); 
    else { 
  
        // Get the command line arguments 
        // and concatenate them 
        printf("%s\n", concat(argv[1], argv[2])); 
    } 
    return 0; 
} 

Java

// Java program to concatenate the two Strings 
// using command line arguments 
  
class GFG { 
  
    // Function to concatenate the String 
    public static String concat(String dest, String src) 
    { 
  
        // Return the concatenated String 
        return (dest + src); 
    } 
  
    // Driver code 
    public static void main(String[] args) 
    { 
  
        // Check if length of args array is 
        // greater than 0 
        if (args.length > 0) { 
  
            // Get the command line arguments 
            // and concatenate them 
            System.out.println(concat(args[0], args[1])); 
        } 
        else
            System.out.println("No command line "
                               + "arguments found."); 
    } 
} 