求 hack

#include <iostream>
#include <cstring>
#define int long long

using namespace std;

void init_vars();
void solve(int testcase, ...);

signed main(){
#ifdef files
	freopen(".in", "r", stdin);
	freopen(".out", "w", stdout);
#endif
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	solve(1);
#ifdef files
	fclose(stdin); fclose(stdout);
#endif
	return 0;
}

int dp[5000024], val[10][10];
char s[10][10];

int calc(int x, int y){
	if(x <= 3 && y <= 3) return (1 << 18);
	if(x <= 3 && y <= 6) return (1 << 19);
	if(x <= 6 && y <= 3) return (1 << 20);
	if(x <= 6 && y <= 6) return (1 << 21);
	return 0;
}

void init_vars(){
	memset(dp, 0x3f3f3f3f, sizeof(dp));
	for(int i = 1; i <= 9; i++){
		for(int j = 1; j <= 9; j++)
			val[i][j] = (1 << (i - 1)) + (1 << (8 + j)) + calc(i, j);
	}
}


int min(int x, int y){
	if(x < y) return x;
	return y;
}

void solve(int testcase, ...){
	init_vars();
	for(int i = 1; i <= 9; i++)
		scanf("%s", s[i]);
	int curr = 0;
	for(int i = 1; i <= 9; i++){
		for(int j = 1; j <= 9; j++){
			if(s[i][j - 1] == '1'){
				curr ^= (1 << (i - 1)) + (1 << (8 + j)) + calc(i, j);
			}
		}
	}
	dp[0] = 0;
	for(int i = 0; i < (1 << 22); i++){
		if(dp[i] != dp[5000023])
			for(int x = 1; x <= 9; x++)
				for(int y = 1; y <= 9; y++)
					dp[i ^ val[x][y]] = min(dp[i] + 1, dp[i ^ val[x][y]]);
	}
	for(int i = (1 << 22) - 1; i >= 1; i--)
		if(dp[i] != dp[5000023])
			for(int x = 1; x <= 9; x++)
				for(int y = 1; y <= 9; y++)
					dp[i ^ val[x][y]] = min(dp[i] + 1, dp[i ^ val[x][y]]);
	printf("%lld\n", dp[curr]);
}

/*
 *  things to check
 *  1. CZY's brain
 *  2. ...
 **/
 
 /*
 *  something to think about
 *  1. how to fix my brain?
 **/

/*
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