HDU 3900 Unblock Me

来源：互联网发布：芭比布朗和mac化妆刷编辑：程序博客网时间：2024/05/17 22:22
http://acm.hdu.edu.cn/showproblem.php?pid=3900
状压BFS。。。
#include<cstdio>#include<cstring>#include<iostream>using namespace std;#define ll long longstruct data{    int t,l,c;  ///t---type 0:heng 1:shu    l:length}B[3545];       ///c:weizhiint n,r;    ///red block#include<map>#include<queue>#include<set>map<ll,bool > vis;ll s;inline bool check(ll s,int x)   /// Xth block{    int tx=(s&(7ll<<(x*3)))>>(x*3);    for(int i=0;i<n;i++)    {        if(i==x) continue;        int ti=(s&(7ll<<(i*3)))>>(i*3);        if(B[x].t==B[i].t) {            if(B[x].c!=B[i].c) continue;            if(tx+B[x].l<=ti||ti+B[i].l<=tx) continue;            return 0;        } else {            if(tx+B[x].l>B[i].c&&B[i].c>=tx&&               ti<=B[x].c&&B[x].c<B[i].l+ti) {                return 0;            }        }    }    return 1;}inline bool done(ll s){    for(int i=0;i<n;i++) {        if(B[i].t==1) continue;        int tt= ((s&(7ll<<(3*r)))>>(r*3));        if(B[i].c<tt+B[r].l) continue;        int l=((s&(7ll<<(3*i)))>>(i*3)) , r=l+B[i].l;        if(r<=2||l>2) continue;        return 0;    }    return 1;}inline void cover(ll& s,int x,int p){    s&=~(7ll<<(x*3));    s|=(ll)p<<(x*3);}#define pii  pair<ll,int>#define  mp  make_pairint bfs(ll s){    if(done(s)) return 1;    queue< pii  > q;    q.push(mp(s,0));    vis.clear();    vis[s]=1;    while(!q.empty()) {        pii tt=q.front(); q.pop();        ll u=tt.first;        int d=tt.second+1;        for(int i=0;i<n;i++) {            int p=(u&(7ll<<(i*3)))>>(i*3);            for(int j=1;j<=p;j++) {                ll v=u;                cover(v,i,p-j);                if(!check(v,i)) break;                if(done(v)) return d+1;                if(vis[v]) continue;                vis[v]=1;                q.push(mp(v,d));            }            for(int j=1;p+j+B[i].l<=6;j++) {                ll v=u;                cover(v,i,p+j);                if(!check(v,i)) break;                if(done(v)) return d+1;                if(vis[v]) continue;                vis[v]=1;                q.push(mp(v,d));            }        }    }    return -1;}int main(){    while(cin>>n&&n)    {       ll s=0;     //  cout<<s<<endl;        for(int i=0;i<n;i++)        {            int t,lx,ly,rx,ry;            cin>>t>>lx>>ly>>rx>>ry;            if(lx==rx) {                B[i].t=0;                B[i].l=ry-ly+1;                B[i].c=lx;                s|=((ll)ly<<(3*i));            }            else {                B[i].t=1;                B[i].l=rx-lx+1;                B[i].c=ly;                s|=((ll)lx<<(3*i));            }          //  cout<<"done:"<<done(s)<<endl;        }        cin>>r;       // print(s);        cout<<bfs(s)<<endl;    }}
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