其他操作只需标记即可
但对于Query操作，非法序列一定是)))(这种形式，所以（=1，）=-1维护前缀和即可（即视感，然而我还是不会QAQ）
调了大半天。。药丸
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],ll[NM],lr[NM],rr[NM],rl[NM],s[NM],b[NM],f[NM],cg[NM],tag[NM],z[NM],a[NM],tmp[NM]; 17 int n,_x,_y,_t,root,tot,t1,t2,m; 18 char st[NM]; 19 void pushdown(int x){ 20 if(x==0)return; 21 if(tag[x]){ 22 swap(ll[x],rl[x]);swap(rr[x],lr[x]); 23 swap(c[x][0],c[x][1]); 24 tag[c[x][0]]^=1;tag[c[x][1]]^=1; 25 tag[x]=0; 26 } 27 if(cg[x]){ 28 s[x]=cg[x]*b[x]; 29 ll[x]=rl[x]=max(0,cg[x]*b[x]); 30 lr[x]=rr[x]=min(0,cg[x]*b[x]); 31 a[x]=cg[x]; 32 cg[c[x][0]]=cg[c[x][1]]=cg[x]; 33 cg[x]=z[x]=z[c[x][0]]=z[c[x][1]]=0; 34 } 35 if(z[x]){ 36 swap(ll[x],lr[x]);ll[x]=-ll[x];lr[x]=-lr[x]; 37 swap(rr[x],rl[x]);rl[x]=-rl[x];rr[x]=-rr[x]; 38 a[x]=-a[x];s[x]=-s[x]; 39 if(cg[c[x][0]])cg[c[x][0]]*=-1;else z[c[x][0]]^=1; 40 if(cg[c[x][1]])cg[c[x][1]]*=-1;else z[c[x][1]]^=1; 41 z[x]=0; 42 } 43 } 44 void up(int i){ 45 a[0]=b[0]=ll[0]=lr[0]=rr[0]=rl[0]=s[0]=0; 46 int x=c[i][0],y=c[i][1]; 47 pushdown(x);pushdown(y); 48 b[i]=b[x]+b[y]+1; 49 s[i]=s[x]+a[i]+s[y]; 50 ll[i]=max(ll[x],s[x]+a[i]+ll[y]); 51 lr[i]=min(lr[x],s[x]+a[i]+lr[y]); 52 rl[i]=max(rl[y],s[y]+a[i]+rl[x]); 53 rr[i]=min(rr[y],s[y]+a[i]+rr[x]); 54 } 55 void newnode(int r,int fa,int k){ 56 f[r]=fa;a[r]=k;b[r]=1;s[r]=k; 57 ll[r]=rl[r]=max(a[r],0); 58 lr[r]=rr[r]=min(a[r],0); 59 } 60 int build(int fa,int x,int y){ 61 int t=x+y>>1; 62 if(x>y)return 0; 63 c[t][0]=build(t,x,t-1); 64 newnode(t,fa,tmp[t]); 65 c[t][1]=build(t,t+1,y); 66 up(t); 67 return t; 68 } 69 int _d(int x){ 70 return c[f[x]][1]==x; 71 } 72 void rot(int x){ 73 int y=f[x],kind=!_d(x); 74 pushdown(y);pushdown(x); 75 c[y][!kind]=c[x][kind];f[c[x][kind]]=y; 76 c[f[y]][_d(y)]=x;f[x]=f[y]; 77 c[x][kind]=y;f[y]=x; 78 up(y);up(x); 79 } 80 void splay(int x,int goal=0){ 81 for(int y=f[x];y!=goal;y=f[x]){ 82 if(f[y]!=goal) 83 _d(x)==_d(y)?rot(y):rot(x); 84 rot(x); 85 } 86 if(goal==0)root=x; 87 } 88 int find(int x){ 89 int r=root; 90 while(x){ 91 pushdown(r); 92 if(b[c[r][0]]>=x)r=c[r][0]; 93 else{ 94 x-=b[c[r][0]]+1; 95 if(!x)return r; 96 r=c[r][1]; 97 } 98 } 99 } 100 int pick(int x,int y){ 101 y+=2;x=find(x);y=find(y); 102 splay(x);splay(y,x); 103 return c[y][0]; 104 } 105 void ch(int x,int y){ 106 int r=pick(x,y); 107 cg[r]=_t;tag[r]=0;z[r]=0; 108 up(y);up(x); 109 } 110 void down(int x,int y){ 111 int r=pick(x,y); 112 tag[r]^=t1; 113 if(cg[r])cg[r]-=cg[r];else z[r]^=t2; 114 up(f[r]);up(f[f[r]]); 115 } 116 void query(int x,int y){ 117 int r=pick(x,y); 118 printf("%d ",(-lr[r]+1)/2+(rl[r]+1)/2); 119 } 120 void out(int x){ 121 pushdown(x); 122 if(c[x][0])out(c[x][0]); 123 printf("%d ",x); 124 // printf("%d %d %d %d %d %d ",x,ll[x],lr[x],rl[x],rr[x],s[x]); 125 if(c[x][1])out(c[x][1]); 126 } 127 int main(){ 128 // freopen("data.in","r",stdin); 129 n=read();m=read(); 130 scanf("%s ",st+2); 131 inc(i,2,n+1)tmp[i]=st[i]=='('?1:-1; 132 build(0,1,n+2);root=(n+3)/2; 133 // out(root);printf(" "); 134 while(m--){ 135 scanf("%s",st); 136 _x=read();_y=read(); 137 if(st[0]=='R'){ 138 scanf("%s",st); 139 _t=st[0]=='('?1:-1; 140 ch(_x,_y); 141 }else if(st[0]=='Q')query(_x,_y); 142 else{ 143 t1=0,t2=0; 144 if(st[0]=='S')t1=1;else t2=1; 145 down(_x,_y); 146 } 147 // out(root);printf(" "); 148 } 149 return 0; 150 }