Program to reverse a string in java?

Answer 1

package sara78;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.util.Scanner;

import java.lang.IndexOutOfBoundsException;

public class node extends RuntimeException{

private static String string;

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

InputStreamReader input = new InputStreamReader(System.in);

BufferedReader reader = new BufferedReader(input);

try {

string = reader.readLine();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

char[] c=string.toCharArray();

int k=c.length;

for(int i=0;i<=k;i++)

{

System.out.println(""+c[i]);

}

for(int i=k;i<=k;--i)

{

System.out.println(""+c[i]);

}

}

}

As well, you could do it with a different approach, same idea:

import java.util.*;

public class Example

{

public static void main(String[] args)

{

Scanner in = new Scanner(System.in);

System.out.println("Please enter a String to reverse:");

String toReverse = in.next();

String Reversed = "";

for (int i = toReverse.length()-1; i>=0; i--)

{

Reversed = Reversed + toReverse.charAt(i);

}

System.out.println(Reversed);

}

}

Answer 2

public class ReverseStringTest {

public static void main(String[] args) {

String str = "What's going on?";

System.out.println(ReverseString.reverseIt(str));

}

}

class ReverseString {

public static String reverseIt(String source) {

int i, len = source.length();

StringBuffer dest = new StringBuffer(len);

for (i = (len - 1); i >= 0; i--)

dest.append(source.charAt(i));

return dest.toString();

}

}

Answer 3

import java.util.*;

public class Example

{

public static void main(String[] args)

{

Scanner in = new Scanner(System.in);

System.out.println("Please enter a string to reverse:");

String input = in.next();

String reversed = "";

for (int i = 0; i<input.length(); i++)

{

reversed = input.charAt(i) + reversed;

}

System.out.println("The reversed string is: " + reversed);

}

}

Answer 4

int[] iArrNumbers = new int[5];

for(int iLoop = 0; iLoop < 5; iLoop++)

iArrNumbers[iLoop] = (iLoop + 4) * (((iLoop + 1) * (iLoop + 1) * 4) + 4); // increasing but not adjacent

// So now the array is: 32, 100, 240, 476, 832

// Reverse in a simple (although perhaps not the most efficient manner)
List lstNumbers = Arrays.asList(iArrNumbers);

Collections.reverse(lstNumbers);

for(int iLoop = 0, iLength = lstNumbers.size(); iLoop < iLength; iLoop++)

iArrNumbers[iLoop] = lstNumbers.get(iLoop);

// iArrNumbers is now: 832, 476, 240, 100, 32 (my math beside the point)

Answer 5

public static final String reverseString(final String str) {

return new StringBuilder(str).reverse().toString();

}

Answer 6

Collections.reverse(list);