BZOJ1932 [Shoi2007]Setstack 集合堆栈机

妈呀。。。clj大爷太强啦！

原来还有set_union和set_intersection这种东西。。。

于是只要把栈顶的每个元素hash一下记录到一个vector里去就好了

 

/**************************************************************
    Problem: 1932
    User: rausen
    Language: C++
    Result: Accepted
    Time:148 ms
    Memory:3372 kb
****************************************************************/
 
#include <cstdio>
#include <vector>
#include <stack>
#include <algorithm>
 
using namespace std;
typedef unsigned long long ull;
typedef vector <ull> vec;
const int N = 2e3 + 5;
const int base = 2333;
 
inline ull add(const vec &v) {
    static ull res;
    static int i;
    for (i = res = 0; i < v.size(); ++i)
        res *= base, res += v[i] + 101;
    return res;
}
 
inline void get(vec &v) {
    sort(v.begin(), v.end());
    v.resize(unique(v.begin(), v.end()) - v.begin());
}
 
int n, top;
vec S[N];
 
int main() {
    int i;
    char st[15];
    vec a, b, c(N);
    scanf("%d",&n);
    for (i = 1; i <= n; ++i) {
        scanf("%s", st + 1);
        if (st[1] == 'P') {
            S[++top] = vec();
            goto end;
        }
        if (st[1] == 'D') {
            ++top, S[top] = S[top - 1];
            goto end;
        }
        a = S[top--], b = S[top--];
        if (st[1] == 'A') {
            b.push_back(add(a)), get(b);
            S[++top] = b;
            goto end;
        }
        c = vec(a.size() + b.size());
        if (st[1] == 'U') {
            c.resize(set_union(a.begin(), a.end(), b.begin(), b.end(), c.begin()) - c.begin());
            get(c), S[++top] = c;
            goto end;
        }
        if (st[1] == 'I') {
            c.resize(set_intersection(a.begin(), a.end(), b.begin(), b.end(), c.begin()) - c.begin());
            get(c), S[++top] = c;
            goto end;
        }
        end : printf("%d\n", S[top].size());
    }
    return 0;
}