#include <stdio.h>

int main() {
    //실습2,4//
    /*printf("Hello world!\n");
    printf("안녕하세요\n");
    printf("1234567890\n");
    printf("abcdefg\n");*/

    //실습3,5//
     printf("Hello world\n안녕하세요.\n1234567890\n abcdefg\n");
    return 0;
}