C 解法, 执行用时: 2ms, 内存消耗: 360KB, 提交时间: 2020-12-23

#include<stdio.h>

int fun(int n)
{
    int count=0;
    while(n>=5){
        count+=n/5;
        n=n/5;
    }
    return count;
}


int main()
{
    int n;
    scanf("%d",&n);
    int count=0;
    if(n>=5){
        for(int i=5;i<=n;i++)
            count+=fun(i);
    }
    printf("%d",count);
    return 0;
}

C 解法, 执行用时: 2ms, 内存消耗: 360KB, 提交时间: 2020-03-19

#include<stdio.h>

int fun(int n)
{
    int count=0;
    while(n>=5){
        count+=n/5;
        n=n/5;
    }
    return count;
}


int main()
{
    int n;
    scanf("%d",&n);
    int count=0;
    if(n>=5){
        for(int i=5;i<=n;i++)
            count+=fun(i);
    }
    printf("%d",count);
    return 0;
}