The number of zero hdu1241 factorial

About number theory, the expression is basically ignorant, the most important thing is to have the idea of several, the problem of the numbers are converted to the idea of prime numbers, but there is no, so it is good to brush questions, slowly cultivate it.

The bottom 0 can only be 2*5=10, 2 appears more than 5, so calculate 5 appears in 1~n How many times, where 25=5*5 (2 times), 50=5*5*2;75=5*5*3, and so on.

eg:124/5=24;

24/5=4;

4/5=0.

There are always some stems to be understood by themselves .....

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1#include <cstdio>2#include <iostream>3 using namespacestd;4 intMain ()5 {6     intn,t;7Cin>>T;8      while(t--)9     {TenCin>>N; One         intres=0; A          while(n/5) -         { -res+=n/5; theN/=5; -         } -cout<<res<<Endl; -     } +     return 0; -}

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The number of zero hdu1241 factorial