python/TangDou/CSP-J/AcWingTraining/T6/TD3.cpp

#include <bits/stdc++.h>
using namespace std;
bool judge(int x) {
    while (x > 0) {
        if (x % 10 == 7) {
            return true;
        }
        x /= 10;
    }
    return false;
}
int main() {
    int L, R, cnt;
    scanf("%d%d", &L, &R);
    for (int i = L; i <= R; i++) {
        if (judge(i)) {
            printf("%d\n", i);
            cnt++;
        }
    }
    if (cnt == 0) {
        printf("None\n");
    }
    return 0;
}