PHP Examples

PHP 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 function 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.

<?php
//function for floyd triangle
function FloydTriangle($n){
  $value = 1;
  for($i = 1; $i <= $n; $i++) {
    for($j = 1; $j <= $i; $j++) {
      echo "$value "; 
      $value++;
    }
    echo "\n"; 
  }
}

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




5