HDU-2234 无题I

为每个状态定义两个函数S和H，分别表示当前状态到列一致和行一致的目标状态的最少操作次数。

然后有了估价函数F=Min(S,H)就可以IDA*了。

#include <cstdio>
#include <iostream>
#include <fstream>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <queue>

#define rep(i, l, r) for(int i=l; i<=r; i++)
#define down(i, l, r) for(int i=l; i>=r; i--)
#define maxn 40320
#define MAX 1<<30

using namespace std;

int t, n[][], k;

inline void Up(int x) { int a; a = n[][x]; n[][x] = n[][x]; n[][x] = n[][x]; n[][x] = n[][x]; n[][x] = a; }
inline void Down(int x) { int a; a = n[][x]; n[][x] = n[][x]; n[][x] = n[][x]; n[][x] = n[][x]; n[][x] = a; }
inline void Right(int x) { int a; a = n[x][]; n[x][] = n[x][]; n[x][] = n[x][]; n[x][] = n[x][]; n[x][] = a; }
inline void Left(int x) { int a; a = n[x][]; n[x][] = n[x][]; n[x][] = n[x][]; n[x][] = n[x][]; n[x][] = a; }

int S()
{
    int b[], o, o2 = ;
    rep(i, , )
    {
        rep(j, , ) b[j] = ; o = ;
        rep(j, , ) b[n[j][i]]++;
        rep(j, , ) o = max(o, b[j]);
        o2 = max(o2, -o);
    }
    return o2;
}

int H()
{
    int b[], o, o2 = ;
    rep(i, , )
    {
        rep(j, , ) b[j] = ; o = ;
        rep(j, , ) b[n[i][j]]++;
        rep(j, , ) o = max(o, b[j]);
        o2 = max(o2, -o);
    }
    return o2;
}

bool Search(int x)
{
    if (x == k)
    {
        if (!S() || !H()) return true; else return false;
    }
    int now = min(S(), H()); if (now > k-x) return false;
    Left(); if (min(S(), H()) <= now) if (Search(x+)) return true; Right();
    Left(); if (min(S(), H()) <= now) if (Search(x+)) return true; Right();
    Left(); if (min(S(), H()) <= now) if (Search(x+)) return true; Right();
    Left(); if (min(S(), H()) <= now) if (Search(x+)) return true; Right();
    Right(); if (min(S(), H()) <= now) if (Search(x+)) return true; Left();
    Right(); if (min(S(), H()) <= now) if (Search(x+)) return true; Left();
    Right(); if (min(S(), H()) <= now) if (Search(x+)) return true; Left();
    Right(); if (min(S(), H()) <= now) if (Search(x+)) return true; Left();
    Up(); if (min(S(), H()) <= now) if (Search(x+)) return true; Down();
    Up(); if (min(S(), H()) <= now) if (Search(x+)) return true; Down();
    Up(); if (min(S(), H()) <= now) if (Search(x+)) return true; Down();
    Up(); if (min(S(), H()) <= now) if (Search(x+)) return true; Down();
    Down(); if (min(S(), H()) <= now) if (Search(x+)) return true; Up();
    Down(); if (min(S(), H()) <= now) if (Search(x+)) return true; Up();
    Down(); if (min(S(), H()) <= now) if (Search(x+)) return true; Up();
    Down(); if (min(S(), H()) <= now) if (Search(x+)) return true; Up();
    return false;
}

int main()
{
    scanf("%d", &t);
    while (t--)
    {
        rep(i, , ) rep(j, , ) scanf("%d", &n[i][j]);
        k = ;
        while (k <= )
            if (Search()) break; else k++;
        if (k == ) k = -; printf("%d\n", k);
    }
    return ;
}