1 #include<cstdio>
2 #define MAXN 500010
3 struct node
4 {
5 int sum;
6 int v1,v0;
7 int left0,left1;
8 int right0,right1;
9 };
10 node tree[MAXN<<2];
11 int cover[MAXN<<2],lazy[MAXN<<2];
12 inline int MAX(int x,int y)
13 {
14 return x>y?x:y;
15 }
16 inline int MIN(int x,int y)
17 {
18 return x>y?y:x;
19 }
20 inline void swap(int &x,int &y)
21 {
22 int temp=x;
23 x=y;
24 y=temp;
25 }
26 inline void PushUp(int mid,int L,int R,int rt)
27 {
28 tree[rt].sum=tree[rt<<1].sum+tree[rt<<1|1].sum;
29 tree[rt].left0=tree[rt<<1].left0;
30 tree[rt].left1=tree[rt<<1].left1;
31 tree[rt].right0=tree[rt<<1|1].right0;
32 tree[rt].right1=tree[rt<<1|1].right1;
33 if(tree[rt].left0==mid-L+1)
34 tree[rt].left0+=tree[rt<<1|1].left0;
35 if(tree[rt].left1==mid-L+1)
36 tree[rt].left1+=tree[rt<<1|1].left1;
37 if(tree[rt].right0==R-mid)
38 tree[rt].right0+=tree[rt<<1].right0;
39 if(tree[rt].right1==R-mid)
40 tree[rt].right1+=tree[rt<<1].right1;
41 tree[rt].v0=MAX(tree[rt<<1].v0,tree[rt<<1|1].v0);
42 tree[rt].v0=MAX(tree[rt].v0,tree[rt<<1].right0+tree[rt<<1|1].left0);
43 tree[rt].v1=MAX(tree[rt<<1].v1,tree[rt<<1|1].v1);
44 tree[rt].v1=MAX(tree[rt].v1,tree[rt<<1].right1+tree[rt<<1|1].left1);
45 }
46 void Build(int L,int R,int rt)
47 {
48 cover[rt]=-1;
49 lazy[rt]=0;
50 if(L==R)
51 {
52 tree[rt].left1=tree[rt].right1=tree[rt].v1=tree[rt].sum=1;
53 tree[rt].left0=tree[rt].right0=tree[rt].v0=0;
54 }
55 else
56 {
57 int mid=(L+R)>>1;
58 Build(L,mid,rt<<1);
59 Build(mid+1,R,rt<<1|1);
60 PushUp(mid,L,R,rt);
61 }
62 }
63 inline void FXOR(int L,int R,int rt)
64 {
65 if(cover[rt]!=-1)
66 {
67 cover[rt]^=1;
68 tree[rt].left1=tree[rt].right1=tree[rt].v1=tree[rt].sum=(R-L+1)*cover[rt];
69 tree[rt].left0=tree[rt].right0=tree[rt].v0=(R-L+1)*(cover[rt]^1);
70 }
71 else
72 {
73 lazy[rt]^=1;
74 tree[rt].sum=R-L+1-tree[rt].sum;
75 swap(tree[rt].left0,tree[rt].left1);
76 swap(tree[rt].right0,tree[rt].right1);
77 swap(tree[rt].v0,tree[rt].v1);
78 }
79 }
80 inline void PushDown(int mid,int L,int R,int rt)
81 {
82 if(cover[rt]!=-1)
83 {
84 cover[rt<<1]=cover[rt<<1|1]=cover[rt];
85 lazy[rt<<1]=lazy[rt<<1|1]=0;
86 tree[rt<<1].left1=tree[rt<<1].right1=tree[rt<<1].v1=tree[rt<<1].sum=(mid-L+1)*cover[rt];
87 tree[rt<<1|1].left1=tree[rt<<1|1].right1=tree[rt<<1|1].v1=tree[rt<<1|1].sum=(R-mid)*cover[rt];
88 tree[rt<<1].left0=tree[rt<<1].right0=tree[rt<<1].v0=(mid-L+1)*(cover[rt]^1);
89 tree[rt<<1|1].left0=tree[rt<<1|1].right0=tree[rt<<1|1].v0=(R-mid)*(cover[rt]^1);
90 cover[rt]=-1;
91 }
92 else if(lazy[rt])
93 {
94 FXOR(L,mid,rt<<1);
95 FXOR(mid+1,R,rt<<1|1);
96 lazy[rt]=0;
97 }
98 }
99 void Update(int x,int y,int val,int L,int R,int rt)
100 {
101 if(x<=L&&R<=y)
102 {
103 cover[rt]=val;
104 lazy[rt]=0;
105 tree[rt].left1=tree[rt].right1=tree[rt].v1=tree[rt].sum=(R-L+1)*val;
106 tree[rt].left0=tree[rt].right0=tree[rt].v0=(R-L+1)*(val^1);
107 }
108 else
109 {
110 int mid=(L+R)>>1;
111 PushDown(mid,L,R,rt);
112 if(mid>=x)
113 Update(x,y,val,L,mid,rt<<1);
114 if(y>mid)
115 Update(x,y,val,mid+1,R,rt<<1|1);
116 PushUp(mid,L,R,rt);
117 }
118 }
119 void Change(int x,int y,int L,int R,int rt)
120 {
121 if(x<=L&&R<=y)
122 FXOR(L,R,rt);
123 else
124 {
125 int mid=(L+R)>>1;
126 PushDown(mid,L,R,rt);
127 if(mid>=x)
128 Change(x,y,L,mid,rt<<1);
129 if(y>mid)
130 Change(x,y,mid+1,R,rt<<1|1);
131 PushUp(mid,L,R,rt);
132 }
133 }
134 int Sum(int x,int y,int L,int R,int rt)
135 {
136 if(x<=L&&R<=y)
137 return tree[rt].sum;
138 int mid=(L+R)>>1,ans=0;
139 PushDown(mid,L,R,rt);
140 if(mid>=x)
141 ans+=Sum(x,y,L,mid,rt<<1);
142 if(y>mid)
143 ans+=Sum(x,y,mid+1,R,rt<<1|1);
144 return ans;
145 }
146 int Query(int x,int y,int L,int R,int rt)
147 {
148 if(x<=L&&R<=y)
149 return tree[rt].v1;
150 int mid=(L+R)>>1,ans=0;
151 PushDown(mid,L,R,rt);
152 if(mid>=x)
153 ans=MAX(ans,Query(x,y,L,mid,rt<<1));
154 if(y>mid)
155 ans=MAX(ans,Query(x,y,mid+1,R,rt<<1|1));
156 ans=MAX(ans,MIN(mid-x+1,tree[rt<<1].right1)+MIN(y-mid,tree[rt<<1|1].left1));
157 return ans;
158 }
159 int main()
160 {
161 char ch;
162 int n,m,x,y;
163 while(~scanf("%d%d",&n,&m))
164 {
165 Build(1,n,1);
166 while(m--)
167 {
168 scanf(" %c%d%d",&ch,&x,&y);
169 if(ch=='C')
170 Update(x,y,0,1,n,1);
171 else if(ch=='S')
172 Update(x,y,1,1,n,1);
173 else if(ch=='A')
174 Change(x,y,1,n,1);
175 else if(ch=='Q')
176 printf("%d\n",Sum(x,y,1,n,1));
177 else
178 printf("%d\n",Query(x,y,1,n,1));
179 }
180 }
181 return 0;
182 }
