hdu3487Play with Chain(splay)

链接

简单的两种操作，一种删除某段区间，加在第I个点的后面，另一个是翻转区间。都是splay的简单操作。

悲剧一：pushdown时候忘记让lz=0

悲剧二：删除区间，加在某点之后的时候忘记修改其父亲节点。

  1 #include <iostream>

  2 #include<cstdio>

  3 #include<cstring>

  4 #include<algorithm>

  5 #include<stdlib.h>

  6 #include<vector>

  7 #include<cmath>

  8 #include<queue>

  9 #include<set>

 10 using namespace std;

 11 #define N 300010

 12 #define LL long long

 13 #define INF 0xfffffff

 14 #define key_value ch[ch[root][1]][0]

 15 const double eps = 1e-8;

 16 const double pi = acos(-1.0);

 17 const double inf = ~0u>>2;

 18 using namespace std;

 19 struct splay_tree

 20 {

 21     int pre[N],size[N];

 22     int ch[N][2];

 23     int root,tot,num,tot1;

 24     int key[N],lz[N];

 25     void dfs(int x)

 26     {

 27         if(x)

 28         {

 29             dfs(ch[x][0]);

 30             printf("结点%2d:左儿子 %2d 右儿子 %2d 父结点 %2d size=%2d,key=%2d lz = %d\n",

 31                    x,ch[x][0],ch[x][1],pre[x],size[x],key[x],lz[x]);

 32             dfs(ch[x][1]);

 33         }

 34     }

 35     void debug()

 36     {

 37         printf("root:%d\n",root);

 38         dfs(root);

 39     }

 40 //以上用于debug*/

 41     void newnode(int &x,int v,int fa)//新建一结点

 42     {

 43         x = ++tot;

 44         ch[x][0]=ch[x][1] = 0;

 45         pre[x] = fa;

 46         lz[x] = 0;

 47         size[x] = 1;

 48         key[x] = v;

 49     }

 50     void pushdown(int w)

 51     {

 52         if(lz[w])

 53         {

 54             int l = ch[w][0],r = ch[w][1];

 55             swap(ch[w][0],ch[w][1]);

 56 

 57             lz[l]^=lz[w];

 58             lz[r]^=lz[w];

 59             lz[w] = 0;

 60         }

 61     }

 62     void pushup(int w)//由儿子更新其父亲

 63     {

 64         size[w] = size[ch[w][0]]+size[ch[w][1]]+1;

 65         //cout<<s[w][0]<<" "<<s[w][1]<<endl;

 66     }

 67     void rotate(int r,int kind)//旋转操作，根据kind进行左旋和右旋

 68     {

 69         int y = pre[r];

 70         pushdown(y);

 71         pushdown(r);

 72         ch[y][!kind] = ch[r][kind];

 73         pre[ch[r][kind]] = y;

 74         if(pre[y])

 75         {

 76             ch[pre[y]][ch[pre[y]][1]==y] = r;

 77         }

 78         pre[r] = pre[y];

 79         ch[r][kind] = y;

 80         pre[y] = r;

 81         pushup(y);

 82         pushup(r);

 83     }

 84     void splay(int r,int goal)//将r结点旋至goal下

 85     {

 86         pushdown(r);

 87         while(pre[r]!=goal)

 88         {

 89             if(pre[pre[r]]==goal)

 90             {

 91                 rotate(r,ch[pre[r]][0]==r);

 92             }

 93             else

 94             {

 95                 int y = pre[r];

 96                 int kind = (ch[pre[y]][0]==y);

 97                 if(ch[y][kind]==r)

 98                 {

 99                     rotate(r,!kind);

100                     rotate(r,kind);

101                 }

102                 else

103                 {

104                     rotate(y,kind);

105                     rotate(r,kind);

106                 }

107             }

108         }

109         pushup(r);

110         if(goal==0) root = r;

111     }

112     int get_k(int k)//得到第k个的结点

113     {

114         int r = root;

115        pushdown(r);

116         while(size[ch[r][0]]+1!=k)

117         {

118             if(size[ch[r][0]]>=k)

119                 r = ch[r][0];

120             else

121             {

122                 k-=(size[ch[r][0]]+1);//根据左右结点的数量来确定第k个节点在哪里

123                 r = ch[r][1];

124             }

125             pushdown(r);

126         }

127         pushup(r);

128         return r;

129     }

130     void cut(int l,int r,int k)

131     {

132         splay(get_k(l),0);

133         splay(get_k(r+2),root);

134         pushdown(ch[root][1]);

135         int nod = key_value;

136         ch[ch[root][1]][0] = 0;

137         pre[nod] = 0;

138         pushup(ch[root][1]);

139         pushup(root);

140         //debug();

141         splay(get_k(k),0);

142         splay(get_k(k+1),root);

143         ch[ch[root][1]][0] = nod;

144         pre[nod] = ch[root][1];

145         pushup(ch[root][1]);

146         pushup(root);

147        // debug();

148     }

149     void filp(int l,int r)

150     {

151         //cout<<get_k(l)<<" "<<get_k(r+2)<<endl;

152         splay(get_k(l),0);

153         splay(get_k(r+2),root); //cout<<","<<endl;debug();

154         lz[key_value]^=1;

155         //swap(ch[key_value][0],ch[key_value][1]);

156         pushup(ch[root][1]);

157         pushup(root);

158     }

159     void work(int n)

160     {

161         int i;

162         for(i = 1 ;i < n ;i++)

163         {

164             printf("%d ",key[get_k(i+1)]);

165         }

166         printf("%d\n",key[get_k(n+1)]);

167         //debug();

168     }

169     void build(int &x,int l,int r,int fa)

170     {

171         int m = (l+r)>>1;

172         if(l>r) return ;

173         newnode(x,m,fa);

174         build(ch[x][0],l,m-1,x);

175         build(ch[x][1],m+1,r,x);

176         pushup(x);

177     }

178     void init(int o)

179     {

180         size[0] = ch[0][0] = ch[0][1] =  key[0] = lz[0] = 0;

181         root = tot = 0;

182         newnode(root,0,0);

183         newnode(ch[root][1],0,root);

184         build(ch[ch[root][1]][0],1,o,ch[root][1]);

185         size[root] = 2;

186         pushup(ch[root][1]);

187         pushup(root);

188     }

189 }SP;

190 int main()

191 {

192     int n,q;

193     while(scanf("%d%d",&n,&q)!=EOF)

194     {

195         if(n==-1&&q==-1) break;

196         SP.init(n);

197         while(q--)

198         {

199             char sq[20];

200             int k,x,y;

201             scanf("%s",sq);

202             if(sq[0]=='C')

203             {

204                 scanf("%d%d%d",&x,&y,&k);

205                 SP.cut(x,y,k+1);

206               // SP.debug();

207 //                SP.work(n);

208             }

209             else

210             {

211                 //SP.debug();

212                 scanf("%d%d",&x,&y);

213                 SP.filp(x,y);

214                 //SP.debug();

215             }

216             //SP.work(n);

217         }

218         SP.work(n);

219     }

220     return 0;

221 }

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