52 lines
1.1 KiB
Java
52 lines
1.1 KiB
Java
import java.util.Scanner;
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/**
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* This program will print out the factorial of any non-negative
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* number that you input into it.
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*
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* @author Unknown
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*
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*/
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public class Factorial{
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/**
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* The main method
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*
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* @param args Command line arguments
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*/
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public static void main(String[] args){
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Scanner input = new Scanner(System.in);
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//Prompt user to enter integer
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System.out.print("Enter a non-negative integer: ");
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//Proceed with factorial calculation only if inputted number is not negative
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if(input.hasNextInt()){
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int number = input.nextInt();
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if (number < 0){
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System.out.print("Cannot execute. Please enter a non-negative integer: ");
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number = input.nextInt();
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} else {
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//Output of factorial for any non-negative number
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System.out.println("The factorial of "+number+" will yield: "+factorial(number));
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}
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}
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}
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/**
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* Recursive Factorial Method
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*
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* @param n The number to factorial
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* @return The factorial of the number
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*/
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public static long factorial(int n){
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if (n==0){
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return 1;
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} else if (n==1){
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return 1;
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} else {
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return n * factorial(n-1);
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}
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}
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} |