Submission #66703252

Source Code Expand

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
#include <stdio.h>
#include <inttypes.h>
int H, W;
uint64_t A[24][24];
uint64_t all = 0;
char put[24][24];
uint64_t calc(int y, int x, uint64_t cur) {
  if (y >= H) {
    return all ^ cur;
  } else if (x >= W) {
    return calc(y + 1, 0, cur);
  } else {
    uint64_t ans, candidate;
    /* 置かない */
    ans = calc(y, x + 1, cur);
    if (!put[y][x]) {
      put[y][x] = 1;
      /* 横に置く */
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

#include <stdio.h>
#include <inttypes.h>

int H, W;
uint64_t A[24][24];

uint64_t all = 0;
char put[24][24];

uint64_t calc(int y, int x, uint64_t cur) {
	if (y >= H) {
		return all ^ cur;
	} else if (x >= W) {
		return calc(y + 1, 0, cur);
	} else {
		uint64_t ans, candidate;
		/* 置かない */
		ans = calc(y, x + 1, cur);
		if (!put[y][x]) {
			put[y][x] = 1;
			/* 横に置く */
			if (x + 1 < W && !put[y][x + 1]) {
				put[y][x + 1] = 1;
				candidate = calc(y, x + 1, cur ^ A[y][x] ^ A[y][x + 1]);
				if (candidate > ans) ans = candidate;
				put[y][x + 1] = 0;
			}
			/* 縦に置く */
			if (y + 1 < H && !put[y + 1][x]) {
				put[y + 1][x] = 1;
				candidate = calc(y, x + 1, cur ^ A[y][x] ^ A[y + 1][x]);
				if (candidate > ans) ans = candidate;
				put[y + 1][x] = 0;
			}
			put[y][x] = 0;
		}
		return ans;
	}
}

int main(void) {
	int i, j;
	if (scanf("%d%d", &H, &W) != 2) return 1;
	for (i = 0; i < H; i++) {
		for (j = 0; j < W; j++) {
			if (scanf("%" SCNu64, &A[i][j]) != 1) return 1;
			all ^= A[i][j];
		}
	}
	printf("%" PRIu64 "\n", calc(0, 0, 0));
	return 0;
}

Submission Info

Judge Result