Gongzhu want to pick herself's boyfriend by Programming Contest.(Well this is for the sake of the baby).Gongzhu give a number Q,and she asks all of boys

to find the minimal natural number N, so that N! contains exactly Q zeroes on the trail in decimal notation. As you know N! = 1*2*...*N. For example, 5! = 120, 120 contains one zero on the trail.

She will marry that person to give the correct answer within 2000MS !

As you love Gongzhu very much ! you want to have a try,Now, you need to solve this problem by programming!!!