Java Program to Display Floyd’s Triangle

Floyd’s triangle is a triangle with first natural numbers. It is the right arrangement of the numbers/values or patterns. Basically, it is a left to right arrangement of natural numbers in a right-angled triangle

Illustration: Suppose if no of rows to be displayed is 5 then the desired output should display 5 rows as:

1
2 3
4 5 6
7 8 9 10
11 12 13 14 15

Algorithm:

1. Initialization of variables
   • Create variables in memory holding rows and columns.
   • Create and initialize variable holding patterns or values to be displayed.
2. Traversing over rows and columns using nested for loops.
   • Outer loop for rows.
   • Inner loop for columns in the current row.
3. Dealing with variable holding dynamic values as per execution as initialized outside nested loops.
   • If values are to be displayed, increment this variable inside the loop for rows and outside loop for columns.
   • If patterns are to be displayed, assign the character outside loop while creation and no alternation of holder value in any of loops.

Implementation: Floyd’s Triangle

Example 

// Java program to display Floyd's triangle

// Importing Java libraries
import java.util.*;

// Main class 
class GFG {

    // Main driver method
    public static void main(String[] args)
    {
        // No of rows to be printed
        int n = 5;

        // Creating and initializing variable for
        // rows, columns and display value
        int i, j, k = 1;

        // Nested iterating for 2D matrix
        // Outer loop for rows
        for (i = 1; i <= n; i++) {

            // Inner loop for columns
            for (j = 1; j <= i; j++) {

                // Printing value to be displayed
                System.out.print(k + "  ");

                // Incremeting value displayed
                k++;
            }

            // Print elements of next row
            System.out.println();
        }
    }
}

1  
2  3  
4  5  6  
7  8  9  10  
11  12  13  14  15

Time Complexity: O(n²) for given n

Auxiliary Space: O(1)