hdu 3397 Sequence operation

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线段树

和UVA那题01串是一样的

记录的信息后，0，1的总数，前缀0和前缀1的总数，后缀0和后缀1的总数，最长0和最长1的长度

对于交换操作，就是总数，前缀，后缀，最长长度对应的0，1的数目交换

设置3个lazy记录之前是进行了变0，变1，取反操作即可

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#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
#define N 100010
#define lson(i) ((i)<<1)
#define rson(i) ((i)<<1|1)

struct SegTree{
	int l,r,mid,len;
	int sum[2],pre[2],suf[2],Max[2];
	bool lazy[3];
	SegTree(){}
	SegTree(int __l,int __r){
		l = __l; r = __r; mid = (l+r) >> 1; len = r - l + 1;
		for(int i = 0; i < 2; i++) 
			sum[i] = pre[i] = suf[i] = Max[i] = 0;
		for(int i = 0; i < 3; i++)
			lazy[i] = false;
	}
}t[N<<2];

void Reverse(int rt){
	swap(t[rt].sum[0],t[rt].sum[1]);
	swap(t[rt].pre[0],t[rt].pre[1]);
	swap(t[rt].suf[0],t[rt].suf[1]);
	swap(t[rt].Max[0],t[rt].Max[1]);
	t[rt].lazy[2] = true;
	t[rt].lazy[0] = t[rt].lazy[1] = false;
}

void Del(int rt,int val){
	if(val == 0){
		t[rt].lazy[0] = true; t[rt].lazy[1] = t[rt].lazy[2] = false;
		t[rt].sum[0] = t[rt].pre[0] = t[rt].suf[0] = t[rt].Max[0] = t[rt].len;
		t[rt].sum[1] = t[rt].pre[1] = t[rt].suf[1] = t[rt].Max[1] = 0;
	}
	else{
		t[rt].lazy[1] = true; t[rt].lazy[0] = t[rt].lazy[2] = false;
		t[rt].sum[1] = t[rt].pre[1] = t[rt].suf[1] = t[rt].Max[1] = t[rt].len;
		t[rt].sum[0] = t[rt].pre[0] = t[rt].suf[0] = t[rt].Max[0] = 0;
	}
}

void PushUp(SegTree &A,SegTree L,SegTree R){
	for(int i = 0; i < 2; i++)
		A.sum[i] = L.sum[i] + R.sum[i];
	//pre[0],suf[0]
	A.pre[0] = L.pre[0]; A.suf[0] = R.suf[0];
	if(L.pre[0] == L.len){
		A.pre[0] = L.len + R.pre[0];
	}
	if(R.suf[0] == R.len){
		A.suf[0] = L.suf[0] + R.len;
	}
	//pre[1],suf[1]
	A.pre[1] = L.pre[1]; A.suf[1] = R.suf[1];
	if(L.pre[1] == L.len){
		A.pre[1] = L.len + R.pre[1];
	}
	if(R.suf[1] == R.len){
		A.suf[1] = L.suf[1] + R.len;
	}
	//Max[0],Max[1]
	A.Max[0] = max(max(L.Max[0],R.Max[0]) , L.suf[0]+R.pre[0]);
	A.Max[1] = max(max(L.Max[1],R.Max[1]) , L.suf[1]+R.pre[1]);
}

void PushDown(int rt){
	if(t[rt].lazy[0]){
		Del(lson(rt),0);
		Del(rson(rt),0);
		t[rt].lazy[0] = false;
	}
	if(t[rt].lazy[1]){
		Del(lson(rt),1);
		Del(rson(rt),1);
		t[rt].lazy[1] = false;
	}
	if(t[rt].lazy[2]){
		if(t[lson(rt)].lazy[0])
			Del(lson(rt),1);
		else if(t[lson(rt)].lazy[1])
			Del(lson(rt),0);
		else if(t[lson(rt)].lazy[2]){
			Reverse(lson(rt));  t[lson(rt)].lazy[2] = false;
		}
		else Reverse(lson(rt));
		
		if(t[rson(rt)].lazy[0])
			Del(rson(rt),1);
		else if(t[rson(rt)].lazy[1])
			Del(rson(rt),0);
		else if(t[rson(rt)].lazy[2]){
			Reverse(rson(rt)); t[rson(rt)].lazy[2] = false;
		}
		else Reverse(rson(rt));
		
		t[rt].lazy[2] = false;
	}
}

void build(int rt,int a,int b){
	t[rt] = SegTree(a,b);
	if(a == b){
		int x;
		scanf("%d",&x);
		if(x == 0){
			t[rt].sum[0] = t[rt].pre[0] = t[rt].suf[0] = t[rt].Max[0] = 1;
			t[rt].lazy[0] = true;
		}
		else{
			t[rt].sum[1] = t[rt].pre[1] = t[rt].suf[1] = t[rt].Max[1] = 1;
			t[rt].lazy[1] = true;
		}
		return ;
	}
	int mid = t[rt].mid;
	build(lson(rt),a,mid);
	build(rson(rt),mid+1,b);
	PushUp(t[rt],t[lson(rt)],t[rson(rt)]);
}

SegTree query(int rt,int a,int b){
	if(t[rt].l == a && t[rt].r == b){
		return t[rt];
	}
	PushDown(rt);
	int mid = t[rt].mid;
	if(b <= mid){
		return query(lson(rt),a,b);
	}
	else if(a  > mid){
		return query(rson(rt),a,b);
	}
	else{
		SegTree L = query(lson(rt),a,mid);
		SegTree R = query(rson(rt),mid+1,b);
		SegTree A = SegTree(a,b);
		PushUp(A,L,R);
		return A;
	}
}

void updata_set(int rt,int a,int b,int val){
	if(t[rt].l == a && t[rt].r == b){
		Del(rt,val);
		return ;
	}
	PushDown(rt);
	int mid = t[rt].mid;
	if(b <= mid)
		updata_set(lson(rt),a,b,val);
	else if(a > mid)
		updata_set(rson(rt),a,b,val);
	else{
		updata_set(lson(rt),a,mid,val);
		updata_set(rson(rt),mid+1,b,val);
	}
	PushUp(t[rt],t[lson(rt)],t[rson(rt)]);
}

void updata_reverse(int rt,int a,int b){
	if(t[rt].l == a && t[rt].r == b){
		if(t[rt].lazy[0])      Del(rt,1);
		else if(t[rt].lazy[1]) Del(rt,0);
		else if(t[rt].lazy[2]){
			Reverse(rt); t[rt].lazy[2] = false;
		}
		else Reverse(rt);
		return ;
	}
	PushDown(rt);
	int mid = t[rt].mid;
	if(b <= mid)
		updata_reverse(lson(rt),a,b);
	else if(a > mid)
		updata_reverse(rson(rt),a,b);
	else{
		updata_reverse(lson(rt),a,mid);
		updata_reverse(rson(rt),mid+1,b);
	}
	PushUp(t[rt],t[lson(rt)],t[rson(rt)]);
}

int main(){
	int n,q,cas;
	scanf("%d",&cas);
	while(cas--){
		scanf("%d%d",&n,&q);
		build(1,0,n-1);
		while(q--){
			int op,a,b;
			scanf("%d%d%d",&op,&a,&b);
			if(op == 0 || op == 1){
				int val = (op == 0 ? 0 : 1);
				updata_set(1,a,b,val);
			}
			else if(op == 2){
				updata_reverse(1,a,b);
			}
			else{
				SegTree res = query(1,a,b);
				if(op == 3) printf("%d\n",res.sum[1]);
				else        printf("%d\n",res.Max[1]);
			}
		}
	}
	return 0;
}