一个整数阶乘N!末尾有多少个0

#include <stdio.h>

#include <stdlib.h>

int Count0(int N)

{

int ret = 0, i, j;

for(i = 1; i <= N; i++)

{

j = i;

while(j % 5 == 0)

{

ret++;

j /= 5;

}

}

return ret;

}

int Count02(int N)

{

int ret = 0;

while(N)

{

ret += N / 5;

N /= 5;

}

return ret;

}

int main()

{

int num = Count02(10);

printf("num = %d\n", num);

return 0;

}