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用10！这个数字做思考，发现每五个数得到一个0，总结规律
z=n/5+n/(5*5)+n/(5*5*5)+…+(直到n小于n的a次幂) //来源公式之美
代码如下：
class Solution {
public:
/*
* @param n: A long integer
* @return: An integer, denote the number of trailing zeros in n!
*/
long long trailingZeros(long long n) {
// write your code here, try to do it without arithmetic operators.
long num = 0;
while(n > 0) {
num += n / 5;
n /= 5;
}
return num;
}
};
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转播
