#include<bits/stdc++.h> using namespace std ; int main ( ) { int A , b = 0 ; int count = 0 ; cin >> A ; if ( A % 5 == 0 ) { while ( 1 ) { if ( A % 5 == 0 ) { count ++ ; A /= 5 ; } else { break ; } } cout << count << endl ; } else { while ( A ) { if ( A % 10 == 0 ) { count ++ ; } A /= 10 ; }
cout << count << endl ; } return 0 ; }