#include <stdio.h>
// #include <fcntl.h>

int main(int argc, char* argv[]){
    int fin = creat("a.txt",O_RDONLY);
    int fout = creat("b.txt",O_WRONLY);
    int current = 0;
    int total = lseek(fin,0,SEEK_END)
    lseek(fin,0,SEEK_SET)
    char tab[20];
    int a = 0;
    char c;
    int i = 0;
    int h1 = 1;
    int h = 1;
    while(current < total){
        i = 0;
        h1 = 1;
        while(h1 && a != -1){
            a = read(fin,&c,1);
            if(c != '\n' && a!=-1){
                tab[i] = c;
                h1 = 1;
            }
            else{
                h1 = 0;
            }
            i++;
        }
        current = current + i;
        while(i>0){
            write(fout, tab[i], 1);
            i--;
        }
        write(fout, '\n', 1);
    }
    close(fin);
    close(fout);
    return 0;
}