#include<bits/stdc++.h> using namespace std; int main(){ int n, m; int sum = 0; cin >> n >> m; for(int i = n; i <= m; i++){ // 接下来需要判断i是否是不吉利的数 int tmp = i; while(tmp != 0){ int g = tmp % 10; int sg = tmp % 100; if(g == 4 || sg == 62){ sum++; break; } tmp /= 10; } } cout << m - n +1 -sum; return 0; }