Question

Write a Java program that prompts the user for an int n. You can assume that 1 ≤ n ≤ 9. Your program should use embedded for loops that produce the following output: 1 2 1 3 2 1 4 3 2 1 5 4 3 2 1 . . . n . . . 5 4 3 2 1 Your prompt to the user should be: Please enter a number 1...9 : Please note that your class should be named PatternTwo.

Answer 1

Answer:

Here is the JAVA program:

import java.util.Scanner;  // to take input from user

public class PatternTwo{   //class name

public static void main(String args[]){  //start of main function

Scanner scan = new Scanner(System.in);   // creates Scanner class object

System.out.print("Please enter a number: ");  //prompts user to enter an int n for the number of rows

int n = scan.nextInt();   //reads and scans the value of n from user

int i, j;   //declares two variables to iterate through i  rows and j columns

for (i=1; i<=n; i++){    //outer loop for rows  

for (j=2*(n-i); j>=1; j--){   //inner loop for space between numbers in pattern  

System.out.print(" ");  }   //displays an empty space in the pattern

for (j = i; j >= 1; j--)  { //inner loop for columns  

System.out.print(j+" "); }   //prints the value of j (prints numbers in reverse)

System.out.println();   }   }   }  //prints a new line after printing each row

Explanation:

The program is explained with an example in the attached document.