You are required to write a program that demonstrates the use of loops and String objects.
Write a program that accepts a string input of 3 characters from the user via the keyboard. Your program will print all permutations of inputted String with repetition and your code should be reusable.
For reference, an illustration of the execution has been shown below:
import java.util.Scanner;
public class StringPermutations {
public StringPermutations()
{
}
/**
* Generates and prints all permutations with repetition for the input string.
*
* @param input the string with 3 characters
*/
public void generatePermutations(String input)
{
int length = input.length();
for (int i = 0; i < length; i++)
{
for (int j = 0; j < length; j++)
{
for (int k = 0; k < length; k++)
{
String result = "" + input.charAt(i) + input.charAt(j) + input.charAt(k);
System.out.println(result);
}
}
}
}
/**
* Main method to run the program.
*
* @param args command-line arguments
*/
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a 3-character string: ");
String input = scanner.nextLine();
if (input.length() != 3)
{
System.out.println("Error: Input must be exactly 3 characters.");
}
else
{
StringPermutations generator = new StringPermutations();
generator.generatePermutations(input);
}
scanner.close();
}
@Override
public String toString() {
return "StringPermutations{}";
}
}课程目录