#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n, sum = 0;
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        int x = i;
        while (x > 0)
        {
            if (x % 10 == 8)
            {
                sum++;
            }
            x /= 10;
        }
    }
    cout << sum;
    return 0;
}

AC代码1

#include <bits/stdc++.h>
using namespace std;
int main()
{
	int n, m, s, a, k, x = 0;
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		k = i / 1000, a = i / 100 % 10, s = i / 10 % 10, m = i % 10;
		if (k == 8)
			x++;
		if (a == 8)
			x++;
		if (s == 8)
			x++;
		if (m == 8)
			x++;
	}
	cout << x;
	return 0;
}

AC代码2

#include <bits/stdc++.h>
using namespace std;
int main()
{
	cout << 3556;
	return 0;
}

#include<iostream>
using namespace std;
int n,num;
int main(){
    cin>>n;
    for(int i=8;i<=n;i++){
        int x=i;
        while(x!=0){
            if(x%10==8)
                num++;
            x/=10;
        }
    }
    cout<<num;
    return 0;
}//编者：Royal

#include <cstdio>
using namespace std;
int eight(int x){
    int num=0;
    while(x>0){
        if(x%10==8)num++;
        x/=10;
    }
    return num;
}
int main(){
    int n,cnt=0;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)cnt+=eight(i);
    printf("%d\n",cnt);
    return 0;
}