<?php $current_balance = 200; $bet_amount = 1; const MAX_ROUND = 500; for($i = 0;$i<MAX_ROUND;$i++) { $result = mt_rand()%2; if($result == 1) { $current_balance = $current_balance+$bet_amount; $bet_amount = 1; } else { $current_balance = $current_balance-$bet_amount; $bet_amount = $bet_amount*2; } $result = $result == 1 ? 'win' : 'lose'; echo "result: ".$result ; echo " ,bet_amount :".$bet_amount; echo " ,balance : ".$current_balance."\n"; }