Java program to reverse a number :
In this tutorial ,we will learn how to reverse a number in Java. First we will take the number as input from the user, then convert it to a string and reverse it . Then again we will convert it back to integer.
Following steps are using in the program :
-
Get the inger from the user using ‘Scanner’
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Convert it to a string using ‘String.valueOf()’
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Create an empty result string.
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Scan the string converted number character by character using a ‘for’ loop from last to first
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Append each character to the result string.
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After the loop is completed, convert the result string to integer using ‘Integer.valueOf()’
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Print out the result
Java example Program :
import java.util.Scanner;
public class Main {
/**
* Utility functions
*/
static void println(String string) {
System.out.println(string);
}
static void print(String string) {
System.out.print(string);
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
println("Enter a number you want to rotate : ");
int number = sc.nextInt();
String strNumber = String.valueOf(number);
String reverseNumberString = "";
for (int i = strNumber.length() - 1; i >= 0; i--) {
reverseNumberString += strNumber.charAt(i);
}
int reverseNumber = Integer.valueOf(reverseNumberString);
println("Reverse of the number is " + reverseNumber);
}
}
Sample Output :
Enter a number you want to rotate :
125467
Reverse of the number is 764521
Enter a number you want to rotate :
562948
Reverse of the number is 849265
Enter a number you want to rotate :
1
Reverse of the number is 1
Enter a number you want to rotate :
54
Reverse of the number is 45