和上题一样，线段树不能区间翻转？（百度误导人那）
就只能splay了
1 #include<bits/stdc++.h> 2 #define inc(i,l,r) for(int i=l;i<=r;i++) 3 #define dec(i,l,r) for(int i=l;i>=r;i--) 4 #define link(x) for(edge *j=h[x];j;j=j->next) 5 #define mem(a) memset(a,0,sizeof(a)) 6 #define inf 1e9 7 #define succ(x) (1<<x) 8 #define NM 100000+5 9 using namespace std; 10 int read(){ 11 int x=0,f=1;char ch=getchar(); 12 while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();} 13 while(isdigit(ch))x=x*10+ch-'0',ch=getchar(); 14 return x*f; 15 } 16 int c[NM][2],a[NM],b[NM],f[NM],ll[NM],lr[NM],rr[NM],rl[NM],s[NM],z[NM],tag[NM],tmp[NM]; 17 int n,m,_x,_y,_t,root; 18 char st[NM]; 19 void pushdown(int i){ 20 if(!i)return; 21 if(z[i]){ 22 swap(ll[i],lr[i]);swap(rr[i],rl[i]); 23 a[i]*=-1;s[i]*=-1;ll[i]*=-1;lr[i]*=-1;rr[i]*=-1;rl[i]*=-1; 24 z[i]=0;z[c[i][0]]^=1;z[c[i][1]]^=1; 25 } 26 if(tag[i]){ 27 swap(c[i][0],c[i][1]);swap(ll[i],rl[i]);swap(rr[i],lr[i]); 28 tag[i]=0;tag[c[i][0]]^=1;tag[c[i][1]]^=1; 29 } 30 } 31 void up(int r){ 32 a[0]=b[0]=ll[0]=lr[0]=rr[0]=rl[0]=c[0][0]=c[0][1]=0; 33 int x=c[r][0],y=c[r][1]; 34 pushdown(x);pushdown(y); 35 b[r]=b[x]+b[y]+1; 36 s[r]=s[x]+s[y]+a[r]; 37 ll[r]=max(ll[x],s[x]+a[r]+ll[y]); 38 lr[r]=min(lr[x],s[x]+a[r]+lr[y]); 39 rl[r]=max(rl[y],s[y]+a[r]+rl[x]); 40 rr[r]=min(rr[y],s[y]+a[r]+rr[x]); 41 } 42 void newnode(int r,int fa,int k){ 43 a[r]=s[r]=k;b[r]=1;f[r]=fa; 44 if(s[r]==1)ll[r]=rl[r]=1;else rr[r]=lr[r]=-1; 45 } 46 int build(int fa,int x,int y){ 47 int t=x+y>>1; 48 if(x>y)return 0; 49 c[t][0]=build(t,x,t-1); 50 newnode(t,fa,tmp[t]); 51 c[t][1]=build(t,t+1,y); 52 up(t); 53 return t; 54 } 55 int _d(int x){ 56 return c[f[x]][1]==x; 57 } 58 void rot(int x){ 59 int y=f[x],kind=!_d(x); 60 pushdown(x);pushdown(y); 61 c[y][!kind]=c[x][kind];f[c[x][kind]]=y; 62 c[f[y]][_d(y)]=x;f[x]=f[y]; 63 c[x][kind]=y;f[y]=x; 64 up(y);up(x); 65 } 66 void splay(int x,int goal=0){ 67 for(int y=f[x];y!=goal;y=f[x]){ 68 if(f[y]!=goal) 69 _d(x)==_d(y)?rot(y):rot(x); 70 rot(x); 71 } 72 if(!goal)root=x; 73 } 74 int find(int x){ 75 int r=root; 76 while(1){ 77 pushdown(r); 78 if(b[c[r][0]]>=x)r=c[r][0]; 79 else{ 80 x-=b[c[r][0]]+1; 81 if(!x)return r; 82 r=c[r][1]; 83 } 84 } 85 } 86 int pick(int x,int y){ 87 y+=2;x=find(x);y=find(y); 88 splay(x);splay(y,x); 89 return c[y][0]; 90 } 91 void ch(int x,int y){ 92 int r=pick(x,y); 93 if(_t==1)z[r]^=1;else tag[r]^=1; 94 } 95 void query(int x,int y){ 96 int r=pick(x,y); 97 pushdown(r); 98 printf("%d ",(-lr[r]+1)/2+(rl[r]+1)/2); 99 } 100 void out(int r){ 101 if(!r)return; 102 pushdown(r); 103 out(c[r][0]); 104 printf("%d ",max(a[r],0)); 105 out(c[r][1]); 106 } 107 int main(){ 108 // freopen("data.in","r",stdin); 109 n=read();m=read();scanf("%s",st+2); 110 inc(i,2,n+1)tmp[i]=st[i]=='('?1:-1; 111 build(0,1,n+2);root=(n+3)/2; 112 // out(root);printf(" "); 113 while(m--){ 114 _t=read();_x=read();_y=read(); 115 if(!_t)query(_x,_y); 116 else ch(_x,_y); 117 // out(root);printf(" "); 118 } 119 return 0; 120 }