poj 2411 Mondriaan's Dream 状态压缩DP 打表

  将题目转换题意, 有一个M列的墙, 我们需要 使用 1*2 的小矩形 砌成N层高, 有多少不同的方案数量.

  因为只有1*2的砖头, 且只有竖立或者横着放.

  那么我们规定 竖立放置的砖头属于 较高的一层, 且 当前点放置砖头则为1,否则为0

  那么我们可以得出结论:

  对于 I 层 状态 X , 若当前位置为0,则下层必定为1. 则意味着下层必定包含 t = (~X)& Mask 

  对于 I+1 层 状态 Y, 除了包含 状态 t 之外, 剩下标记为1的 必须两两成对.才可符合状态.

  

  注意   t = (~X)& Mask    这里要记得还要与 总集合MASK相与. 把状态限定在MASK之内

解题代码:

View Code
#include<stdio.h>

#include<stdlib.h>

#include<string.h>



typedef long long LL;

typedef unsigned int uint;

const int N = 1<<11;

/*

计算结果代码部分

LL ans[12][12];



LL dp[12][N+10];

int n, m;



bool check( uint x ){

    

    for(uint i = 0; i < m; i++)

    {

        if( x&(1<<i) )

        {

            if( i+1 >= m ) return false;

            if( ( x&(1<<(i+1) ) ) == 0 ) return false;

            i++;

        }

    }

    return true;

}



int main()

{

    freopen("6.out","w",stdout);



    memset( ans, 0, sizeof(ans) );

    for(n = 1; n <= 11; n++)

        for(m = 1; m <= 11; m++)

    {

        memset( dp, 0, sizeof(dp) );

    

        int Max = (1<<m)-1;

        for(int mask = 0; mask <= Max; mask++)

            if( check(mask) ) dp[0][mask] = 1;

    

    //    for(uint i = 0; i < Max; i++)

    //        if( dp[0][i] ) printf("%d ", i); puts("");

    

        for(int h = 0; h < n-1; h++)

        {

            for(uint mask = 0; mask <= Max; mask++)

            {

                if( dp[h][mask] ){

                    uint t = (~mask)&Max;

                    for(uint x = 0; x <= Max; x++)

                    {

                //        printf("mask = %u, t = %u, x = %u\n", mask, t, x );    

                        if( ((x&t)==t) && check( t^x ) ) 

                            dp[h+1][x] += dp[h][mask];    

                    

                    }    

                }    

            }

    //        cur = !cur;    

        }

    //    printf( (n==1&&m==1) ? "%lld" : ",%lld", dp[n-1][Max] );    

        ans[n][m] = dp[n-1][Max];

    }

    printf("{\n");

    for(int i = 0; i <= 11; i++)

    {

        printf("{");    

        for(int j = 0; j <= 11; j++)

        {

            printf( j == 0 ? "%lld" : ",%lld", ans[i][j] );    

        }

        printf( i == 11 ? "}\n" :  "},\n");        

    }

    printf("};\n");    

    return 0;

}

*/

LL ans[12][12] =

{

{0,0,0,0,0,0,0,0,0,0,0,0},

{0,0,1,0,1,0,1,0,1,0,1,0},

{0,1,2,3,5,8,13,21,34,55,89,144},

{0,0,3,0,11,0,41,0,153,0,571,0},

{0,1,5,11,36,95,281,781,2245,6336,18061,51205},

{0,0,8,0,95,0,1183,0,14824,0,185921,0},

{0,1,13,41,281,1183,6728,31529,167089,817991,4213133,21001799},

{0,0,21,0,781,0,31529,0,1292697,0,53175517,0},

{0,1,34,153,2245,14824,167089,1292697,12988816,108435745,1031151241,8940739824},

{0,0,55,0,6336,0,817991,0,108435745,0,14479521761,0},

{0,1,89,571,18061,185921,4213133,53175517,1031151241,14479521761,258584046368,3852472573499},

{0,0,144,0,51205,0,21001799,0,8940739824,0,3852472573499,0}

};



int main()

{

    int n, m;

    while( scanf("%d%d",&n,&m) != EOF)

    {

        if(n+m == 0 ) break;

        printf("%lld\n", ans[n][m]);

    }

    return 0;

}

 

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