Use puts.

src/main.c

@@ -31,12 +31,12 @@ int main(void) {
 		unsigned int a;
 		scanf("%u", &a);
 		if(a == 0) {
-			printf("Goodbye!\n");
+			puts("Goodbye!");
 			return 0;
 		} else if(a != 1 << n) {
-			printf("Wrong answer, try again.\n");
+			puts("Wrong answer, try again.");
 		} else {
-			printf("Correct!\n");
+			puts("Correct!");
 			++n;
 		}
 	}