Help with reversing the characters of a String!!

[Valerie10b]

I have to Input a String from the user (use Scanner class method nextLine). Then, write a for loop that prints the characters of the String in reverse. I'm having trouble printing a string of characters to reverse after the user inputs them. when i put hello its supposed to say olleh, and it isnt. I have 2 other problems in my java application and they work perfectly fine. the only thing that isnt printing in the output is problem 3. the only thing that shows in the output is "Enter the String:" for problem 3, and when i do, nothing happens. What am i doing wrong?? Everything in my program is compiling and running. I'm new to programming, can someone help me and explain please!!!

//
// problem # 1 - print odd numbers from 1 to 99
//

import java.util.Scanner;
public class Lab6A {

public static int Problem1() {

System.out.println ("This is problem # 1\n");
   int x = 1;
   while(x <= 99) {
      System.out.println(x);
      x = x+2;
   }// end while loop
      return x;
   
  } // end


  public static void main (String args[]) {
   
   // Test All Problems 
   Problem1();
   System.out.println ("The odd numbers between 1 and 99");
   Problem2();
   Problem3();
  
            
   }//end
   
   
//
// problem # 2 - print a triangle of asterisks
//

public static void Problem2() {

System.out.println ("\nThis is problem # 2\n");
   Scanner scan = new Scanner(System.in);
      int n =0;
      do {
         System.out.print("Enter a number: ");
      n = scan.nextInt();
      if (n<1 || n>50) {
         System.out.println("Error: Invalid input!");
      }
         } while (n<1 || n>50);

      TestProblem2(n);
 }//end main

   public static void TestProblem2(int base) {
   
      for(int i=1; i <= base; i++) { 
         for(int j=0; j < i; j++) {
            System.out.print("*");
      }//end loop i
               System.out.println();
      }//end loop j
}//end main


//
// problem # 3 - print the character of the string in reverse
//

public static String Problem3() {
System.out.println ("\nThis is problem # 3\n");

   Scanner scan = new Scanner(System.in);
   System.out.println("Enter The String:");
   String s = scan.nextLine();

   for (int i = s.length()-1; i >= 0; i--) 
   {
   s += s.charAt(i);
   }
   return s;

}
 


}//end class

[jim829]

The problem with problem number 3 is you are assigning to the same string that your source string is in. So you are clobbering s. Use a different string variable.

Regards,
Jim

[Valerie10b]

The problem with problem number 3 is you are assigning to the same string that your source string is in. So you are clobbering s. Use a different string variable.

Regards,
Jim

im sorry, but how would i do that. I'm a bit confused

[jim829]

First you are clobbering (or more specifically appending to your s variable). If you want to return just the characters reversed, then don't assign each character back to s. Use a different variable, like r;

String r;
r = .....
...

return r;

// And when you test this routine, use

String v = Problem3();
System.out.println(v);

Regards,
Jim

[DarrylBurke]

Method names should start with a lowercase letter.
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