题解 | #挑7#
挑7
https://www.nowcoder.com/practice/ba241b85371c409ea01ac0aa1a8d957b
#include <iostream>
using namespace std;
int main() {
int a, b=0;
while (cin >> a ) { // 注意 while 处理多个 case
for (int i=1; i<=a; i++) {
if (i%10==7||i%7==0||(i/10)%10==7||(i/100)%10==7||(i/1000)%10==7||(i/10000)%10==7) {
b++;
}
}
cout << b << endl;
}
}
