BZOJ 1018: [SHOI2008]堵塞的交通traffic

#include <iostream>
#include <cstdio>
#include <cstring>
#include <stack>
#include <string.h>
#include <queue>
#include <vector>
#include <algorithm>
#include <cassert>
#include <set>
#include <map>
#include <cmath>
#include <ctime>
using namespace std;
#define rep(i,a,b) for(int i=(a);i<(b);++i)
#define rrep(i,a,b) for(int i=(a);i>=(b);--i)
#define clr(a,x) memset(a,(x),sizeof(a))
#define eps 1e-9
#define LL long long
#define mp make_pair
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
const int maxn=100000+5;

bool lk[maxn<<2][2][2];
bool lr[maxn<<2][2];
bool open[maxn][3];

void PushUp(int l,int m,int r,int rt)
{
int ls=rt<<1,rs=rt<<1|1;
rep(i,0,2) rep(j,0,2) {
lk[rt][i][j]=false;
rep(k,0,2) {
lk[rt][i][j] |= lk[ls][i][k] && open[m][k+1] && lk[rs][k][j];
if(lk[rt][i][j]) break;
}
}
lr[rt][0] = lr[rt][1] = false;
if(open[l][0]) {
lr[rt][0] = true;
rep(i,0,2) rep(j,0,2)
lk[rt][i][j] |= lk[rt][i^1][j];
}
if(open[r][0]) {
lr[rt][1] = true;
rep(i,0,2) rep(j,0,2)
lk[rt][i][j] |= lk[rt][i][j^1];
}
lr[rt][0] |= lr[ls][0] || (lr[rs][0] && open[m][1] && open[m][2] && ((lk[ls][0][0]&&lk[ls][1][1]) || (lk[ls][0][1] && lk[ls][1][0])));
lr[rt][1] |= lr[rs][1] || (lr[ls][1] && open[m][1] && open[m][2] && ((lk[rs][0][0]&&lk[rs][1][1]) || (lk[rs][0][1] && lk[rs][1][0])));
}

void build(int l,int r,int rt)
{
if(l==r) {
rep(i,0,2) rep(j,0,2) lk[rt][i][j]=false;
rep(i,0,2) lk[rt][i][i]=true;
lr[rt][0]=lr[rt][1]=false;
return;
}
int m=(l+r)>>1;
build(lson); build(rson);
PushUp(l,m,r,rt);
}

void update(int L,int R,int l,int r,int rt)
{
if(l==r) {
lr[rt][0]=lr[rt][1]=open[l][0];
rep(i,0,2) lk[rt][i][i^1]=open[l][0];
return;
}
int m=(l+r)>>1;
if(L<=m) update(L,R,lson);
if(m<R) update(L,R,rson);
PushUp(l,m,r,rt);
}

int n;
char op[10];

void DoUpdate(bool on)
{
int r1,r2,c1,c2;
scanf("%d%d%d%d",&r1,&c1,&r2,&c2);
if(r1>r2) swap(r1,r2),swap(c1,c2);
else if(r1==r2&&c1>c2) swap(c1,c2);
if(r1!=r2) open[c1][0]=on;
else open[c1][r1]=on;
update(c1,c2,1,n,1);
}

struct Segment
{
int l,r;
int lk[2][2];
int lr[2];
}sgt[500];
int tot;

void GetSegment(int L,int R,int l,int r,int rt)
{
if(L<=l&&r<=R) {
Segment & st = sgt[tot];
rep(i,0,2) rep(j,0,2) st.lk[i][j]=lk[rt][i][j];
st.l=l,st.r=r;
rep(i,0,2) st.lr[i]=lr[rt][i];
++tot;
return;
}
int m=(l+r)>>1;
if(L<=m) GetSegment(L,R,lson);
if(m<R) GetSegment(L,R,rson);
}

bool DoQuery()
{
int r1,c1,r2,c2; scanf("%d%d%d%d",&r1,&c1,&r2,&c2);
if(r1==r2&&c1==c2) return true;
if(c1>c2) swap(r1,r2),swap(c1,c2);
else if(c1==c2&&r1>r2) swap(r1,r2);
tot = 0;
GetSegment(1,c1,1,n,1);
bool t1=false;
rrep(i,tot-1,0) {
if(sgt[i].lr[1]) { t1=true; break; }
if(i==0) break;
int l=sgt[i].l-1;
if(!open[l][1]||!open[l][2]) break;
if(sgt[i].lk[0][0]&&sgt[i].lk[1][1]) continue;
if(sgt[i].lk[0][1]&&sgt[i].lk[1][0]) continue;
break;
}
tot = 0;
GetSegment(c2,n,1,n,1);
bool t2=false;
rep(i,0,tot) {
if(sgt[i].lr[0]) { t2=true; break; }
if(i==tot-1) break;
int r=sgt[i].r;
if(!open[r][1]||!open[r][2]) break;
if(sgt[i].lk[0][0]&&sgt[i].lk[1][1]) continue;
if(sgt[i].lk[0][1]&&sgt[i].lk[1][0]) continue;
break;
}
int s1=1<<(r1-1),s2=1<<(r2-1);
if(t1) s1=3; if(t2) s2=3;
tot = 0;
GetSegment(c1,c2,1,n,1);
rep(i,0,tot) {
int ret=0;
rep(j,0,2) {
if((s1&(1<<j))==0) continue;
rep(k,0,2) ret |= (sgt[i].lk[j][k]<<k);
}
s1=ret;
if(i<tot-1) {
int r=sgt[i].r;
if(open[r][1]&&open[r][2]) s1 &= 3;
else if(open[r][1]) s1 &= 1;
else if(open[r][2]) s1 &= 2;
else s1 &= 0;
}
if(s1==0) return false;
}
return (s1&s2)>0;
}

void solve()
{
while(scanf("%s",op)==1) {
if(op[0]=='E') break;
if(op[0]=='O') DoUpdate(true);
else if(op[0]=='C') DoUpdate(false);
else puts(DoQuery()?"Y":"N");
}
}

int main()
{
//    freopen("in.txt","r",stdin);
while(scanf("%d",&n)==1) {
clr(open,0); clr(lk,0); clr(lr,0);
build(1,n,1);
solve();
}
}