30 Days Of Code HackerRank Solution 01 in c/c++/java/python

Day 0:  "Hello, World" problem  

Task      
To complete this challenge, you must save a line of input from stdin to a variable, print Hello, World. on a single line, and finally print the value of your variable on a second line.

Input Format     

A single line of text denoting  (the variable whose contents must be printed).

Output Format    

Print Hello, World. on the first line, and the contents of  on the second line.

Sample Input     

Welcome to 30 Days of Code!

Sample Output    

        Hello, World. 

        Welcome to 30 Days of Code!   

Explanation    

On the first line, we print the string literal Hello, World.. On the second line, we print the contents of the  variable which, for this sample case, happens to be Welcome to 30 Days of Code!. If you do not print the variable's contents to stdout, you will not pass the hidden test case.

Solution :

1. Code in c

  #include  stdio.h
  #include  string.h
  #include  math.h
  #include  stdlib.h
          
int main() 
{

    // Declare a variable named 'input_string' to hold our input.          
    char input_string[105]; 
          
    // Read a full line of input from stdin and save it to our variable, input_string.          
    scanf("%[^\n]", input_string); 
          
    // Print a string literal saying "Hello, World." to stdout using printf.
    printf("Hello, World.\n");
          
    // TODO: Write a line of code here that prints the contents of input_string to stdout.
    printf("%s",input_string);
          
return 0;
                   
}

2. Code in c++

  #include vector
  #include iostream
  #include algorithm
  using namespace std;


int main() 
{
      
    // Declare a variable named 'input_string' to hold our input.
    string input_string; 

    // Read a full line of input from stdin (cin) and save it to our variable, input_string.
    getline(cin, input_string); 
      
    // Print a string literal saying "Hello, World." to stdout using cout.
    cout << "Hello, World." << endl;
      
    // TODO: Write a line of code here that prints the contents of input_string to stdout.
    cout << input_string << endl;
      

return 0;
            
}

3. Code in Java

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
          

public class Solution {
          
    public static void main(String[] args) {
          
    // Create a Scanner object to read input from stdin.
    Scanner scan = new Scanner(System.in); 
          
    // Read a full line of input from stdin and save it to our variable, inputString.
    String inputString = scan.nextLine(); 
          
    // Close the scanner object, because we've finished reading          
    // all of the input from stdin needed for this challenge.
    scan.close(); 
          
    // Print a string literal saying "Hello, World." to stdout.
    System.out.println("Hello, World.");
          
    // TODO: Write a line of code here that prints the contents of inputString to stdout.
    System.out.println(inputString);
          

    }
}

4. Code in Python

    # Read a full line of input from stdin and save it to our dynamically typed variable, input_string.         
    input_string = input()
              
    # Print a string literal saying "Hello, World." to stdout.
    print('Hello, World.')
              
    # TODO: Write a line of code here that prints the contents of input_string to stdout.
    print(input_string)