PHP to realize the Russian multiplication example _php skill

This article illustrates the method of Russian multiplication in PHP. Share to everyone for your reference. The specific analysis is as follows:

First, overview:

Russian multiplication is an algorithm that calculates the multiplication of two numbers.
Examples are as follows:
Calculate 35*72
Process
35 72
17 144
8 288
4 576
2 1152
1 2304
From top to bottom, for each row, if the number on the left is odd, then the right side of the number out, add.
72+144+2304=2520
The cumulative result of 2520 is the product.

Second, the implementation code:

<?php
function Russian ($m, $n, $res = 0) {
  (1 = = ($n & 1)) && $res + = $m;
  $m = $m << 1;
  $n = $n >> 1;
  Return $n? Russian ($m, $n, $res): $res;
}
Echo Russian (7, 8);

I hope this article will help you with your PHP program design.