CQOI2013 新数独

// luogu-judger-enable-o2
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<iostream>
#include<cmath>
#include<ctime>
#define rep(i,a,n) for(int i = a;i <= n;i++)
#define per(i,n,a) for(int i = n;i >= a;i--)
#define enter putchar(‘\n‘)

using namespace std;
typedef long long ll;
const int M = 1005;
const int mod = 1e9 + 7;

int read()
{
   int ans = 0,op = 1;
   char ch = getchar();
   while(ch < ‘0‘ || ch > ‘9‘)
   {
      if(ch == ‘-‘) op = -1;
      ch = getchar();
   }
   while(ch >= ‘0‘ && ch <= ‘9‘)
   {
      ans *= 10;
      ans += ch - ‘0‘;
      ch = getchar();
   }
   return ans * op;
}

int num[11][11],hcnt,lcnt,px,py;
int lim[11][11][11],vish[11][11],visl[11][11],visg[11][11];
char s;

void print()
{
   rep(i,1,9)
   {
      rep(j,1,9) printf("%d ",num[i][j]);enter;
   }
}

bool pd(int g,int pos,int k)
{
   rep(j,1,9)
   {
      int dx = g / 3 * 3 + (j - 1) / 3 + 1,dy = g % 3 * 3 + (j - 1) % 3 + 1;
      if(lim[g][pos][j] == 1 && num[dx][dy] && k < num[dx][dy]) return 0;
      if(lim[g][pos][j] == 2 && num[dx][dy] && k > num[dx][dy]) return 0;
   }
   return 1;
}

void buildh(int i,int k)
{
   rep(j,1,6)
   {
      int g = (i - 1) * 3 + ((j - 1) >> 1);
      int pos = ((k - 1) >> 1) * 3 + ((j - 1) & 1) + 1;
      cin >> s;
      lim[g][pos][pos+1] = (s == ‘>‘) ? 1 : 2;
      lim[g][pos+1][pos] = (s == ‘>‘) ? 2 : 1;
   }
}

void buildl(int i,int k)
{
   rep(j,1,9)
   {
      int g = (i - 1) * 3 + (j - 1) / 3;
      int pos = ((k-1) >> 1) * 3 + (j - 1) % 3 + 1;
      cin >> s;
      lim[g][pos][pos+3] = (s == ‘v‘) ? 1 : 2;
      lim[g][pos+3][pos] = (s == ‘v‘) ? 2 : 1;
   }
}

void build()
{
   rep(i,1,3)
      rep(k,1,5)
      (k & 1) ? buildh(i,k) : buildl(i,k);
}

void dfs(int x,int y)
{
   int g = ((x - 1) / 3) * 3 + (y - 1) / 3;
   int pos = (x - 1) % 3 * 3 + (y - 1) % 3 + 1;
   rep(k,1,9)
   {
      if(vish[x][k] || visl[y][k] || visg[g][k]) continue;
      if(!pd(g,pos,k)) continue;
      vish[x][k] = visl[y][k] = visg[g][k] = 1,num[x][y] = k;
      //print();
      if(x == 9 && y == 9) print(),exit(0);
      else (y == 9) ? dfs(x+1,1) : dfs(x,y+1);
      vish[x][k] = visl[y][k] = visg[g][k] = 0,num[x][y] = 0;
   }
}

int main()
{
   build();
   /*rep(i,1,9)
   {
      rep(j,1,9)
      {
     printf("%d ",lim[1][i][j]);
      }
      enter;
   }*/
   dfs(1,1);
   return 0;
}