bzoj2049: [Sdoi2008]Cave 洞穴勘测

  1 #include<iostream>
  2 #include<cstring>
  3 #include<cstdlib>
  4 #include<algorithm>
  5 #include<cstdio>
  6 using namespace std;
  7 
  8 const int Maxn = 10010;
  9 
 10 int ch[Maxn][2],p[Maxn],flip[Maxn];
 11 int n,m;
 12 
 13 const int D=15000000;
 14 char in[D],out[300010*10],*I=in,*O=out;
 15 #define gc (*I++)
 16 #define pc(x) ((*O++)=x)
 17 template <typename Q> 
 18 void gt(Q&x) {
 19     static char c,f;
 20     for(c=gc,f=0;!isdigit(c);c=gc)if(c==‘-‘) f=1;
 21     for(x=0;isdigit(c);c=gc) x=x*10+c-‘0‘;
 22     f && (x=-x);
 23 }
 24 
 25 template <typename Q>
 26 void pt(Q x){
 27     static char stk[20];
 28     static int top;
 29     top=0;
 30     if(x==0) pc(‘0‘);
 31     for(;x;x/=10) stk[++top] = x%10+‘0‘;
 32     for(;top;top--) pc(stk[top]);
 33 }
 34 
 35 void down(int x){
 36     if(flip[x]) {
 37         swap(ch[x][0],ch[x][1]);
 38         flip[ch[x][0]]^=1;
 39         flip[ch[x][1]]^=1;
 40         flip[x]=0;
 41     }
 42 }
 43 
 44 bool isroot(int x){
 45     return ch[p[x]][0]!=x && ch[p[x]][1]!=x;
 46 }
 47 
 48 void rotate(int x) {
 49     int y=p[x],z=p[y];
 50     int l=ch[y][1]==x,r=l^1;
 51     if(!isroot(y)) ch[z][ch[z][1]==y]=x;
 52     p[ch[x][r]]=y;
 53     p[y]=x;
 54     p[x]=z;
 55     
 56     ch[y][l]=ch[x][r];
 57     ch[x][r]=y;
 58 }
 59 
 60 int stk[Maxn],top;
 61 void splay(int x){
 62     stk[top=1]=x;
 63     for(int t=x;!isroot(t);t=p[t]) stk[++top]=p[t];
 64     for(;top;top--) down(stk[top]);
 65     
 66     for(;!isroot(x);){
 67         int y=p[x],z=p[y];
 68         if(!isroot(y)){
 69             if( (ch[y][1]==x)^(ch[z][1]==y) )
 70                 rotate(x);else rotate(y);
 71         }
 72         rotate(x);
 73     }
 74 }
 75 
 76 void access(int x){
 77     for(int t=0;x;x=p[t=x]){
 78         splay(x);
 79         ch[x][1]=t;
 80     }
 81 }
 82 
 83 int getroot(int x){
 84     for(access(x),splay(x);ch[x][0];x=ch[x][0]);
 85     return x;
 86 }
 87     
 88 void newroot(int x) {
 89     access(x);
 90     splay(x);
 91     flip[x]^=1;
 92 }
 93 
 94 void cut(int x){
 95     access(x);
 96     splay(x);
 97     p[ch[x][0]]=0;
 98     ch[x][0]=0;
 99 }
100 
101 void combine(int x,int y) {
102     newroot(x);
103     p[x]=y;
104 }
105 
106 void work() {
107     gt(n),gt(m);
108     char c;
109     int a,b;
110     for(int i=1;i<=m;i++) {
111         for(;c=gc,c!=‘Q‘ && c!=‘C‘ &&c!=‘D‘;);
112         gt(a),gt(b);
113         if(c==‘Q‘) printf("%s\n",getroot(a)==getroot(b)?"Yes" : "No");
114         else if(c==‘C‘) combine(a,b);
115         else newroot(a),cut(b);
116     }
117 }
118 
119 int main() {
120 #ifdef DEBUG
121     freopen("in.txt","r",stdin);
122     freopen("out.txt","w",stdout);
123 #endif
124     fread(in,1,D,stdin);
125     
126     work();
127     
128     return printf(out),0;
129 }