POJ3481 Double Queue

水题

用set和splay都写了一下

set版

 1 #include <set>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <algorithm>
 5 using namespace std;
 6 const int maxn = 300005;
 7 struct node
 8 {
 9     int val,name;
10     bool operator <(const node &rhs)const{
11         return val<rhs.val;
12     }
13 };
14 
15 int main()
16 {
17     set<node>s;
18     int op,b,c;
19     while(~scanf("%d",&op)&&op){
20         if(op==1){
21             scanf("%d%d",&b,&c);
22             s.insert((node){c,b});
23         }
24         else {
25             if(s.empty())printf("0\n");
26             else {
27                 if(op==2){
28                     set<node>::iterator it = s.end();
29                     it--;
30                     printf("%d\n",(*it).name);
31                     s.erase(it);
32                 }
33                 else {
34                     set<node>::iterator it = s.begin();
35                     printf("%d\n",(*it).name);
36                     s.erase(it);
37                 }
38             }
39         }
40     }
41     return 0;
42 }

splay

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <algorithm>
  4 using namespace std;
  5 const int maxn = 200005;
  6 int fa[maxn],son[2][maxn],val[maxn],name[maxn];
  7 int root,tot,cnt;
  8 void rota(int w,int x){
  9     int y = fa[x];
 10     son[!w][y] = son[w][x];
 11     if(son[w][x])fa[son[w][x]] = y;
 12     fa[x] = fa[y];
 13     if(fa[y])son[y==son[1][fa[y]]][fa[y]] = x;
 14     fa[y] = x;
 15     son[w][x] = y;
 16 }
 17 void splay(int x,int y){
 18     while(fa[x]!=y){
 19         if(fa[fa[x]]==y)rota(x==son[0][fa[x]],x);
 20         else {
 21             int w = fa[x]==son[0][fa[fa[x]]];
 22             if(x==son[w][fa[x]]){
 23                 rota(!w,x);rota(w,x);
 24             }
 25             else {
 26                 rota(w,fa[x]);rota(w,x);
 27             }
 28         }
 29     }
 30     if(y==0)root = x;
 31 }
 32 void Ins(int v){
 33     int x = root;
 34     while(1){
 35         if(v<val[x]){
 36             if(son[0][x])x = son[0][x];
 37             else break;
 38         }
 39         else {
 40             if(son[1][x])x = son[1][x];
 41             else break;
 42         }
 43     }
 44     fa[++tot] = x;
 45     val[tot] = v;
 46     if(v<val[x])son[0][x] = tot;
 47     else son[1][x] = tot;
 48     splay(tot,0);
 49 }
 50 int getMax(){
 51     int x = root;
 52     while(1){
 53         if(son[1][x])x = son[1][x];
 54         else break;
 55     }
 56     return x;
 57 }
 58 int getMin(){
 59     int x = root;
 60     while(1){
 61         if(son[0][x])x = son[0][x];
 62         else break;
 63     }
 64     return x;
 65 }
 66 void Del(int x){
 67     splay(x,0);
 68     int y = son[0][x],z = son[1][x];
 69     if(y==0&&z==0){root = 0;return;}
 70     while(son[1][y])y = son[1][y];
 71     while(son[0][z])z = son[0][z];
 72     if(y)splay(y,0);
 73     if(z)splay(z,y);
 74     if(y==0){son[0][z] = 0;return;}
 75     if(z==0){son[1][y] = 0;return;}
 76     son[0][z] = 0;
 77 }
 78 int main()
 79 {
 80     int op,a,b;
 81     while(~scanf("%d",&op)&&op){
 82         if(op==1){
 83             scanf("%d%d",&a,&b);
 84             if(cnt==0)val[root = ++tot] = b;
 85             else Ins(b);
 86             name[tot] = a;
 87             cnt++;
 88         }
 89         else {
 90             if(cnt==0)printf("%d\n",0);
 91             else {
 92                 int x;
 93                 if(op==2)x = getMax();
 94                 else x = getMin();
 95                 printf("%d\n",name[x]);
 96                 Del(x);
 97                 cnt--;
 98             }
 99         }
100     }
101     return 0;
102 }

 

posted on 2015-08-09 20:27  round_0  阅读(131)  评论(0)  编辑  收藏  举报

导航