Length of rope tied around three equal circles touching each other | PHP program to find the length of rope ; Function to find the length of rope ; Driver code
< ? php $ PI = 3.14159265 ; function length_rope ( $ r ) { global $ PI ; return ( ( 2 * $ PI * $ r ) + 6 * $ r ) ; } $ r = 7 ; echo ( length_rope ( $ r ) ) ; ? >