Function to find the shortest distance
< ? php function dist ( $ x1 , $ y1 , $ x2 , $ y2 , $ r ) { echo " The ▁ shortest ▁ distance ▁ between ▁ a ▁ point ▁ and ▁ a ▁ circle ▁ is ▁ " , sqrt ( ( pow ( ( $ x2 - $ x1 ) , 2 ) ) + ( pow ( ( $ y2 - $ y1 ) , 2 ) ) ) - $ r ; }