poj2411(状压dp)

#include<cstdio>
#include<cstring>
using namespace std;

long long dp[10000+10][1<<12];
bool in[1<<20];

int main(){
    int n,m;
    int num;
    while(scanf("%d%d",&n,&m)&&n){
            dp[0][0]=1;
    for (int i = 0; i < 1 << m; i++) {
            bool cnt = 0, has_odd = 0;
            for (int j = 0; j < m; j++)
                if (i >> j & 1) has_odd |= cnt, cnt = 0;//1^0还是1
                else cnt ^= 1;
            in[i] = has_odd|cnt  ? 0 : 1;
        }
           // for (int i=0;i < 1<<m;i++) printf("%d ",in[i]);
        for (int i=1;i<=n;i++){
            for (int j=0;j<(1<<m);j++){
                    dp[i][j]=0;
                for (int k=0;k<(1<<m);k++){
                    if((j&k)==0 && in[j|k]){
                        dp[i][j]+=dp[i-1][k];
                    }
                }
            }
        }
        printf("%lld\n",dp[n][0]);
    }
return 0;
}