#include <stdio.h>

int main() {

    //실습 2,4//
    printf("Hello world!\n");
    printf("안녕하세요\n");
    printf("1234567890\n");
    printf("abcdefg\n");

    //실습 3,5//
    printf("Hello world!\n안녕하세요\n1234567890\nabcdefg\n");
    return 0;

}