poj 2411 (状态压缩)

第一道状态压缩，撒花~~~

/*
 * =====================================================================================
 *
 *       Filename:  a.cpp
 *        Version:  1.0
 *        Created:  2013-08-27 23:01:05
 *       Revision:  none
 *       Compiler:  GNU C++
 *
 *      Just like you,wait you forever~~
 *
 * =====================================================================================
 */
#include <set>
#include <map>
#include <list>
#include <queue>
#include <stack>
#include <cmath>
#include <string>
#include <cstdio>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>

using namespace std;

#define PB             	push_back
#define SIZE(x)        	(int)x.size()
#define clr(x,y)       	memset(x,y,sizeof(x))
#define MP(x,y)     	make_pair(x,y)
#define reads(n)       	scanf ("%s", n)
#define ALL(t)         	(t).begin(),(t).end()
#define FOR(i,n,m)     	for (int i = n; i <= m; i ++)
#define ROF(i,n,m)     	for (int i = n; i >= m; i --)
#define IT             	iterator
#define FF	      	first
#define SS		second

typedef long long               ll;
typedef unsigned int            uint;
typedef unsigned long long      ull;
typedef vector<int>             vint;
typedef vector<string>          vstring;
typedef pair<int, int> 		PII;

void RI (int& x){
        x = 0;
        char c = getchar ();
        while (c == ' '||c == '\n')	c = getchar ();
        bool flag = 1;
        if (c == '-'){
                flag = 0;
                c = getchar ();
        }
        while (c >= '0' && c <= '9'){
                x = x * 10 + c - '0';
                c = getchar ();
        }
        if (!flag)	x = -x;
}
void RII (int& x, int& y){RI (x), RI (y);}
void RIII (int& x, int& y, int& z){RI (x), RI (y), RI (z);}

/**************************************END define***************************************/

const ll mod = 1e9+7;
const ll LINF = 1e18;
const int INF = 1e9;
const double EPS = 1e-8;

const int N = (1 << 11);

int n, m;
ll dp[13][N];
vint g[N];

void init (){
        FOR (i, 0, N-1)         g[i].clear ();
        clr (dp, 0);
}

void dfs (int col, int x, int y){
        if (col > n){
                g[x].PB (y);
                return;
        }
        dfs (col+1, (x<<1)+1, y<<1);
        dfs (col+1, x<<1, (y<<1)+1);
        if (col + 1 <= n)       dfs (col+2, x<<2, y<<2);
}

int main (){
        while (cin >> n >> m, n||m){
                if (m < n)      swap (m, n);
                init ();
                dfs (1, 0, 0);
                dp[1][0] = 1;
                FOR (i, 1, m){
                        FOR (j, 0, (1<<n)-1){
                                FOR (h, 0, SIZE (g[j])-1){
                                        int v = g[j][h];
                               //         cout << j << " " << v << endl;
                                        dp[i+1][v] += dp[i][j];
                                }
                        }
                }
                cout << dp[m+1][0] << endl;
        }
}