int magic = int.Parse(Console.ReadLine()); for (int i = 1; i <= 4; i++) { for (int j = 1; j <= 4; j++) { for (int k = 1; k <= 4; k++) { char s1 = '\0', s2 = '\0', s3 = '\0'; switch (i) { case 1: s1 = 'A'; break; case 2: s1 = 'C'; break; case 3: s1 = 'G'; break; case 4: s1 = 'T'; break; } switch (j) { case 1: s2 = 'A'; break; case 2: s2 = 'C'; break; case 3: s2 = 'G'; break; case 4: s2 = 'T'; break; } switch (k) { case 1: s3 = 'A'; break; case 2: s3 = 'C'; break; case 3: s3 = 'G'; break; case 4: s3 = 'T'; break; } char ends = (i + j + k >= magic) ? 'O' : 'X'; Console.Write($"{ends}{s1}{s2}{s3}{ends} "); } Console.WriteLine(); } }