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Java Program to print Floyd’s Triangle

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Write a Java Program to print Floyd’s Triangle with example. The Floyd’s Triangle is a right angled triangle with array of natural numbers.

Java Program to print Floyd’s Triangle

This Java program allows the user to enter the maximum number of rows he/she want to print as Floyd’s triangle and then, this program will print the Floyd’s triangle of natural numbers until it reaches the user specified rows.

// Java Program to print Floyd’s Triangle
package ShapePrograms;

import java.util.Scanner;

public class FloydTriangle {
	private static Scanner sc;
	
	public static void main(String[] args) {
		int  rows, i,  j, number = 1;
		sc = new Scanner(System.in);		
		System.out.println(" Please Enter the Number of Rows you wish to see in FloydTriangle:  ");
		rows = sc.nextInt();
		System.out.println("---- Printing FLOYD'S Triangle ------");
		for ( i = 1 ; i <= rows; i++ ){
			for ( j = 1 ; j <= i; j++ ) {
				System.out.format("%d ", number);
				number++;
			}
			System.out.println("");
		}
	}
}

OUTPUT

Java Program to print Floyd Triangle 1

ANALYSIS

Following statements will allow the User to enter the range or maximum Number of rows he/she want to print.

System.out.println(" Please Enter the Number of Rows you wish to see in FloydTriangle:  ");
rows = sc.nextInt();

Now let us see the Nested for loop in Java

for ( i = 1 ; i <= rows; i++ ){
	for ( j = 1 ; j <= i; j++ ) {
		System.out.format("%d ", number);
		number++;
	}
	System.out.println("");
}

Outer For Loop – First Iteration

From the above screenshot you can observe that, The value of i is 1 and Rows is 5 so, the condition (i <= 5) is True. So, it will enter into second for loop

Inner For Loop – First Iteration

The j value is 1 and the condition (j <= 1) is True. So, it will start executing the statements inside the loop. Following statement will print Number as Output and we all know that, Number = 1 so, 1 is printed

System.out.format("%d ", number);

Following statement will increment the Value of Number by 1 using the Increment Operator

number++;

Inner For Loop – Second Iteration

The j value will be 2 and the condition (2 <= 1) is False so it will exit from the second loop.

Following statement is used to terminate the current line

System.out.println("");

Outer For Loop – Second Iteration

The value of i will be 2 and the condition (2 <= 5) is True. So, it will enter into second for loop

Inner For Loop – First Iteration

The value of j is 1 and the condition (1 <= 2) is True. So, it will start executing the statements inside the loop. Following statement will print Number as Output and we all know that, Number = 2 so, 2 is printed

System.out.format("%d ", number);

Following statement will increment the Value of Number by 1

number++;

Next, j value will also be incremented by 1.

Inner For Loop – Second Iteration

The value of j is 2 and the condition (2 <= 2) is True. So, it will start executing the statements inside the loop. It means, 3 will be printed.

Inner For Loop – Third Iteration

The j value will be 3 and the condition (3 <= 2) is False so it will exit from the second loop.

This will happen until it reaches to 5 and after that both the Inner Loop and Outer loop will be terminated.

Java Program to Print Floyd’s Triangle using Functions

This Java program allows the user to enter the maximum number of rows he/she want to print as Floyd’s triangle and then, this program will print the Floyd’s triangle of natural numbers using Functions

package ShapePrograms;

import java.util.Scanner;

public class FloydTriangleusingMethods {
	private static Scanner sc;
	
	public static void main(String[] args) {
		int  rows;
		sc = new Scanner(System.in);		
		System.out.println(" Please Enter the Number of Rows you wish to see in FloydTriangle:  ");
		rows = sc.nextInt();
		
		System.out.println("---- Printing FLOYD'S Triangle ------");
		FloydTriangle(rows);		
	}
	
	public static void FloydTriangle (int rows)  {
		int  i,  j, number = 1;
		for ( i = 1 ; i <= rows; i++ )  {
			for ( j = 1 ; j <= i; j++ )  {
				System.out.format("%d ", number);
				number++;
			}
			System.out.println("");
		}
	}
}

OUTPUT

Java Program to print Floyd Triangle 2

ANALYSIS

When the compiler reaches to FloydTriangle(rows); line then the compiler will immediately jump to below function:

public static void FloydTriangle (int rows)  {

We already explained the LOGIC in above example.

NOTE: If we create a function with Void then there is no need to return any value but, if we declared a function with any data type (int, float etc) then we have to return something out from the function.

Java Program to Print Floyd’s Triangle without Natural numbers

This Java program allows the user to enter the number of rows he/she want to display as Floyd’s triangle. In this example we are going to print the Floyd’s triangle using the * symbol. This program can also be said as printing Right angled triangle with * symbol’s.

// Floyd’s Triangle program in Java
package ShapePrograms;

import java.util.Scanner;

public class FloydTrianglewithoutNumbers {
	private static Scanner sc;
	
	public static void main(String[] args) {
		int  rows, i,  j;
		sc = new Scanner(System.in);		
		System.out.println(" Please Enter the Number of Rows you wish to see in FloydTriangle:  ");
		rows = sc.nextInt();
		
		System.out.println("---- Printing FLOYD'S Triangle ------");
		for ( i = 1 ; i <= rows; i++ ) {
			for ( j = 1 ; j <= i; j++ ) {
				System.out.format("* ");
			}
			System.out.println("");
		}
	}
}

OUTPUT

Java Program to print Floyd Triangle 3