문제 출처 :
https://www.acmicpc.net/problem/2739
#include <iostream>
#define range(x) (1 <= x && x <= 9)
using namespace std;
int main(){
int N;
cin >> N;
if(range(N)){
for(int i = 1 ; i<=9 ; i++){
cout << N << " * " << i << " = " << i * N << endl ;
}
}
return 0 ;
}
https://github.com/gurcks8989/BackJoon/blob/master/Step/03.for%EB%AC%B8/P01_2739.cpp