思路：
恶心；
代码：
#include <bits/stdc++.h> using namespace std; #define maxn 100005 struct TreeNodeType { int l,r,l1,r1,m1,l0,r0,m0,mid,size,cnt1,cnt0; bool f1,f0,ff; inline void turn(){swap(l1,l0),swap(r1,r0),swap(m1,m0),swap(cnt1,cnt0);} inline void turn1(){l0=0,r0=0,m0=0,cnt0=0,l1=size,r1=size,m1=size,cnt1=size;} inline void turn0(){l1=0,r1=0,m1=0,cnt1=0,l0=size,r0=size,m0=size,cnt0=size;} inline void F1(){f1=true,f0=false,ff=false;} inline void F0(){f0=true,f1=false,ff=false;} inline void FF(){ if(f1) f0=true,f1=false; else if(f0) f1=true,f0=false; else ff^=1; } inline void turnzero(){f1=false,f0=false,ff=false;} }; struct TreeNodeType tree[maxn<<2]; struct AnsType { int l,r,m,s; }; int n,m,Count; inline void in(int &now) { char Cget=getchar();now=0; while(Cget>'9'||Cget<'0') Cget=getchar(); while(Cget>='0'&&Cget<='9') now=now*10+Cget-'0',Cget=getchar(); } inline void updata(int now) { tree[now].cnt1=tree[now<<1].cnt1+tree[now<<1|1].cnt1; tree[now].cnt0=tree[now<<1].cnt0+tree[now<<1|1].cnt0; tree[now].l1=tree[now<<1].size==tree[now<<1].l1?tree[now<<1].l1+tree[now<<1|1].l1:tree[now<<1].l1; tree[now].l0=tree[now<<1].size==tree[now<<1].l0?tree[now<<1].l0+tree[now<<1|1].l0:tree[now<<1].l0; tree[now].r1=tree[now<<1|1].size==tree[now<<1|1].r1?tree[now<<1|1].r1+tree[now<<1].r1:tree[now<<1|1].r1; tree[now].r0=tree[now<<1|1].size==tree[now<<1|1].r0?tree[now<<1|1].r0+tree[now<<1].r0:tree[now<<1|1].r0; tree[now].m1=max(tree[now<<1].r1+tree[now<<1|1].l1,max(tree[now<<1].m1,tree[now<<1|1].m1)); tree[now].m0=max(tree[now<<1].r0+tree[now<<1|1].l0,max(tree[now<<1].m0,tree[now<<1|1].m0)); } inline void downdata(int now) { if(tree[now].f1) tree[now<<1].turn1(),tree[now<<1|1].turn1(),tree[now<<1].F1(),tree[now<<1|1].F1(); if(tree[now].f0) tree[now<<1].turn0(),tree[now<<1|1].turn0(),tree[now<<1].F0(),tree[now<<1|1].F0(); if(tree[now].ff) tree[now<<1].turn(),tree[now<<1|1].turn(),tree[now<<1].FF(),tree[now<<1|1].FF(); tree[now].turnzero(); } inline void build(int now,int l,int r) { tree[now].l=l,tree[now].r=r,tree[now].size=r-l+1; if(l==r) { int pos; in(pos); if(pos) tree[now].l1=1,tree[now].r1=1,tree[now].m1=1,tree[now].cnt1=1; else tree[now].l0=1,tree[now].r0=1,tree[now].m0=1,tree[now].cnt0=1; return; } tree[now].mid=l+r>>1; build(now<<1,l,tree[now].mid); build(now<<1|1,tree[now].mid+1,r); updata(now); } inline void operation0(int now,int l,int r) { if(tree[now].l>=l&&tree[now].r<=r){tree[now].turn0(),tree[now].F0();return;} if(tree[now].f1||tree[now].f0||tree[now].ff) downdata(now); if(l<=tree[now].mid) operation0(now<<1,l,min(r,tree[now].mid)); if(r>tree[now].mid) operation0(now<<1|1,max(tree[now].mid+1,l),r); updata(now); } inline void operation1(int now,int l,int r) { if(tree[now].l>=l&&tree[now].r<=r){tree[now].turn1(),tree[now].F1();return;} if(tree[now].f1||tree[now].f0||tree[now].ff) downdata(now); if(l<=tree[now].mid) operation1(now<<1,l,min(r,tree[now].mid)); if(r>tree[now].mid) operation1(now<<1|1,max(tree[now].mid+1,l),r); updata(now); } inline void operation2(int now,int l,int r) { if(tree[now].l>=l&&tree[now].r<=r){tree[now].turn(),tree[now].FF();return;} if(tree[now].f1||tree[now].f0||tree[now].ff) downdata(now); if(l<=tree[now].mid) operation2(now<<1,l,min(r,tree[now].mid)); if(r>tree[now].mid) operation2(now<<1|1,max(tree[now].mid+1,l),r); updata(now); } inline void operation3(int now,int l,int r) { if(tree[now].l>=l&&tree[now].r<=r){Count+=tree[now].cnt1;return;} if(tree[now].f1||tree[now].f0||tree[now].ff) downdata(now); if(l<=tree[now].mid) operation3(now<<1,l,min(r,tree[now].mid)); if(r>tree[now].mid) operation3(now<<1|1,max(l,tree[now].mid+1),r); updata(now); } inline AnsType operation4(int now,int l,int r) { if(tree[now].l>=l&&tree[now].r<=r) return (AnsType){tree[now].l1,tree[now].r1,tree[now].m1,tree[now].size}; if(tree[now].f1||tree[now].f0||tree[now].ff) downdata(now); bool al=false,ar=false;AnsType Al,Ar,res; if(l<=tree[now].mid) al=true,Al=operation4(now<<1,l,min(r,tree[now].mid)); if(r>tree[now].mid) ar=true,Ar=operation4(now<<1|1,max(l,tree[now].mid+1),r); if(al&&ar) { res.s=Al.s+Ar.s; res.l=Al.s==Al.l?Al.l+Ar.l:Al.l; res.r=Ar.s==Ar.r?Ar.r+Al.r:Ar.r; res.m=max(Al.r+Ar.l,max(Al.m,Ar.m)); return res; } return al?Al:Ar; } int main() { in(n),in(m),build(1,0,n-1); int op,l,r;AnsType pos; while(m--) { in(op),in(l),in(r); if(op==0) operation0(1,l,r); if(op==1) operation1(1,l,r); if(op==2) operation2(1,l,r); if(op==3) Count=0,operation3(1,l,r),printf("%d ",Count); if(op==4) pos=operation4(1,l,r),printf("%d ",max(max(pos.l,pos.r),pos.m)); } return 0; }