Java Examples

Java Program - Print Floyd's Triangle



Floyd's triangle is named after Robert Floyd and it is a right-angled triangular array of natural numbers. It is created by filling the rows of the triangle with consecutive natural numbers, starting with 1 at the top.

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

Example:

In the example below, a method called FloydTriangle is defined. It requires one parameter to pass as number of rows in the triangle and prints the given number of rows of Floyd's triangle.

public class MyClass  {
  //method for floyd triangle
  static void FloydTriangle(int n) {
    int value = 1;
    for(int i = 1; i <= n; i++) {
      for(int j = 1; j <= i; j++) {
        System.out.print(value + " "); 
        value++;
      }
      System.out.println(); 
    }
  }  
  public static void main(String[] args) {
    FloydTriangle(7);
  }
}

The above code will give the following output:

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15 
16 17 18 19 20 21 
22 23 24 25 26 27 28