POJ 1038 状压DP

​​​http://poj.org/problem?id=1038​​

#include<cstdio>
#include<cstring>
int const N=200;
int const M=20;
int map[N][M];
int bin[12];
int p[20],p1[20],p2[20],p3[20],p4[20],n,m,k,f1[60000],f2[60000];
void three(int x){
    for (int i=1;i<=m;++i){
        p[i]=x%3;
        x=x/3;
    }
}
int ten(int p[]){
    int ans=0;
    for (int i=1;i<=m;++i){
        ans+=p[i]*bin[i];
    }
    return ans;
}
int max(int a,int b){
    if (a<b) return b;
    return a;
}
void dfs1(int x,int s){
    if (x>m){
        for (int i=1;i<=m;++i){
            if (p3[i]==1) p4[i]=2;
            if (p3[i]!=1&&p2[i]==1) p4[i]=1;
            if (p3[i]==0&&p2[i]==0) p4[i]=0;

        }
        f2[ten(p4)]=max(s,f2[ten(p4)]);
        return;
    }
    //不放
    dfs1(x+1,s);
    // 竖放
    if(x<m&&(p1[x]==0)&&(p2[x]==0)&&(p3[x]==0)&&(p1[x+1]==0)&&(p2[x+1]==0)&&(p3[x+1]==0)){
        p1[x]=p2[x]=p3[x]=p3[x+1]=p2[x+1]=p1[x+1]=1;
        dfs1(x+2,s+1);
        p1[x]=p2[x]=p3[x]=p3[x+1]=p2[x+1]=p1[x+1]=0;
    } 
    //横放 
    if(x<m-1&&(p2[x]==0)&&(p2[x+1]==0)&&(p2[x+2]==0)&&(p3[x+2]==0)&&(p3[x+1]==0)&&(p3[x]==0)){
        p2[x+2]=p2[x]=p3[x]=p3[x+1]=p2[x+1]=p3[x+2]=1;
        dfs1(x+3,s+1);
        p2[x+2]=p2[x]=p3[x]=p3[x+1]=p2[x+1]=p3[x+2]=0;
    } 
}
int main(){
    //freopen("poj1038.in","r",stdin);
    //freopen("poj3018.out","w",stdout);
    int t,state;
    scanf("%d",&t);
    bin[1]=1;
    for (int i=2;i<=11;++i){
        bin[i]=bin[i-1]*3;
    }
    while (t--){
        scanf("%d%d%d",&n,&m,&k);
        memset(map,0,sizeof(map));
        for (int i=1;i<=k;++i){
            int x,y;
            scanf("%d%d",&x,&y);
            map[x][y]=1;
        }
        state=bin[m+1]-1;
        memset(f1,-1,sizeof(f1));
        f1[state]=0;
        for (int i=1;i<=n;++i){
            memset(f2,-1,sizeof(f2));
            for (int j=0;j<=state;++j){
                if (f1[j]==-1) continue;
                three(j);
                for (int z=1;z<=m;++z){
                    if (p[z]==2) {
                        p1[z]=1;p2[z]=1;continue;
                    }
                    if (p[z]==1){
                        p1[z]=1;p2[z]=0;continue;
                    }

                    p1[z]=0;p2[z]=0;
                }
                for (int z=1;z<=m;++z){
                    p3[z]=map[i][z];
                }
                dfs1(1,f1[j]);
            }
            memcpy(f1,f2,sizeof(f2));    

        }
        int ans=-1;
        for (int i=0;i<=state;++i){
            if (ans<f2[i]) ans=f2[i];
        }
        printf("%d\n",ans);
    }
    return 0;
}