UVa 12096 (STL) The SetStack Computer

 1 #include <cstdio>
 2 #include <string>
 3 #include <vector>
 4 #include <stack>
 5 #include <set>
 6 #include <map>
 7 #include <iostream>
 8 #include <algorithm>
 9 using namespace std;
10 
11 typedef set<int> Set;
12 map<Set, int> IDcache;
13 vector<Set> Setcache;
14 
15 #define ALL(x) x.begin(),x.end()
16 #define INS(x) inserter(x,x.begin())
17 
18 int ID(Set x)
19 {
20     if(IDcache.count(x)) return IDcache[x];
21     Setcache.push_back(x);
22     return IDcache[x] = Setcache.size() - 1;
23 }
24 
25 int main()
26 {
27     //freopen("in.txt", "r", stdin);
28 
29     int T;
30     scanf("%d", &T);
31     while(T--)
32     {
33         stack<int> s;
34         int n;
35         scanf("%d", &n);
36         for(int i = 0; i < n; ++i)
37         {
38             string op;
39             cin >> op;
40             if(op[0] == ‘P‘) s.push(ID(Set()));
41             else if(op[0] == ‘D‘) s.push(s.top());
42             else
43             {
44                 Set x1 = Setcache[s.top()]; s.pop();
45                 Set x2 = Setcache[s.top()]; s.pop();
46                 Set x;
47                 if(op[0] == ‘U‘) set_union(ALL(x1), ALL(x2), INS(x));
48                 if(op[0] == ‘I‘) set_intersection(ALL(x1), ALL(x2), INS(x));
49                 if(op[0] == ‘A‘) { x = x2; x.insert(ID(x1)); }
50                 s.push(ID(x));
51             }
52             printf("%d\n", Setcache[s.top()].size());
53         }
54 
55         puts("***");
56     }
57 
58     return 0;
59 }