clock.c

#include <stdio.h>
#include <string.h>

#define MAX_SQUARE 57521883
#define C1 4617
#define C2 73
#define C3 36936
#define C4 262657
#define C5 2134536
#define C6 16810048
#define C7 2363904
#define C8 19136512
#define C9 18911232

typedef long square;

#define PRINT(x)\
	while (s##x--)\
	{\
		sprintf(tmp, #x " ");\
		strcat(result, tmp);\
	}

#define ITER_HEAD(x, y)\
	for (s##x = 0, r##x = r##y; s##x < 4; s##x++)\
	{\
		now += s##x;\
		if (now > mins)\
		{\
			now -= s##x;\
			break;\
		}

#define ITER_END(x)\
		turn(&r##x, C##x);\
		now -= s##x;\
	}

void turn(square *des, square clock)
{
	*des = (*des + clock) & MAX_SQUARE;
}

char match(square a)
{
	return a == 0;
}

int main()
{
	FILE *fin, *fout;
	int s1, s2, s3, s4, s5, s6, s7, s8, s9;
	square r0 = 0, r1, r2, r3, r4, r5, r6, r7, r8, r9;
	int mins = 28, now = 0;
	char result[55] = {0}, tmp[3], p_result[55] = {0};

	fin = fopen("clocks.in", "r");
	fout = fopen("clocks.out", "w");

	for (s1 = 0; s1 < 3; s1++)
		for (s2 = 0; s2 < 3; s2++)
		{
			fscanf(fin, "%d", &s3);
			r0 += ((s3 % 12) / 3) << ((s1 * 3 + s2) * 3);
		}
	ITER_HEAD(1, 0)
	ITER_HEAD(2, 1)
	ITER_HEAD(3, 2)
	ITER_HEAD(4, 3)
	ITER_HEAD(5, 4)
	ITER_HEAD(6, 5)
	ITER_HEAD(7, 6)
	ITER_HEAD(8, 7)
	ITER_HEAD(9, 8)
		if (match(r9))
		{
			PRINT(1)
			PRINT(2)
			PRINT(3)
			PRINT(4)
			PRINT(5)
			PRINT(6)
			PRINT(7)
			PRINT(8)
			PRINT(9)
			if (now < mins)
			{
				mins = now;
				strcpy(p_result, result);
			}
			else if (now == mins && strcmp(result, p_result) < 0)
				strcpy(p_result, result);
		}
	ITER_END(9)
	ITER_END(8)
	ITER_END(7)
	ITER_END(6)
	ITER_END(5)
	ITER_END(4)
	ITER_END(3)
	ITER_END(2)
	ITER_END(1)
	p_result[strlen(p_result) - 1] = '\0';
	fprintf(fout, "%s\n", p_result);

	fclose(fin);
	fclose(fout);

	return 0;
}