BZOJ1932——[Shoi2007]Setstack 集合堆栈机

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1、题目大意：就是给你一个栈，有一些操作，向栈加入空集，把栈顶的元素复制一遍再加入栈，求栈顶两元素的并集，交集
还有栈的第一个元素和栈顶（将栈顶压缩成一个元素）
2、分析：这个其实不是用hash做的，是用系统地一堆函数做的。。
我用hash做的，其实就是暴力的hash，用ULL，用了一堆的STL。。。。不要去重，然后RKhash的长度记得取模

#include <cstdio>#include <cstdlib>#include <cstring> #include <algorithm>#include <vector>#include <stack> using namespace std;#define ULL unsigned long long#define ygorz pair<ULL, int>stack<vector<ygorz> > st;char str[20];ygorz qaq[200000];ULL power[200000];int main() {    int n;    scanf("%d", &n);    power[0] = 1;    for (int i = 1; i <= 199900; i++) power[i] = power[i - 1] * 107;    for (int i = 1; i <= n; i++) {        scanf("%s", str);        if (str[0] == 'P') {            vector<ygorz> a;            a.clear();            st.push(a);        }        else if (str[0] == 'D') {            st.push(st.top());        }        else if (str[0] == 'U') {            vector<ygorz> a = st.top(); st.pop();            vector<ygorz> b = st.top(); st.pop();            int u = 0, v = 0;            int wt = 0;            while (u < a.size() || v < b.size()) {                if (u == a.size()) {                    qaq[++wt] = b[v];                    v++;                }                else if (v == b.size()) {                    qaq[++wt] = a[u];                    u++;                }                else {                    if (a[u] < b[v]) {                        qaq[++wt] = a[u];                        u++;                    }                    else if (a[u] > b[v]) {                        qaq[++wt] = b[v];                        v++;                    }                    else {                        qaq[++wt] = a[u];                        u++; v++;                    }                }            }            vector<ygorz> c;            if(wt){                c.clear();                for (int i = 1; i <= wt; i++){                    c.push_back(qaq[i]);                }                }            st.push(c);        }        else if (str[0] == 'I') {            vector<ygorz> a = st.top(); st.pop();            vector<ygorz> b = st.top(); st.pop();            int u = 0, v = 0;            /*for (; u < a.size(); u++)            {                for (; v < b.size()&&b[v] < a[u]; v++);                if (v < b.size()&&a[u] == b[v]) c.push_back(a[u]);            }            */            int wt = 0;            while (u < a.size() || v < b.size()) {                if (u == a.size()) {                // qaq[++wt] = b[v];                 v++;                }                else if (v == b.size()) {                // qaq[++wt] = a[u];                 u++;                }                else {                    if (a[u] < b[v]) {            //         qaq[++wt] = a[u];                     u++;                    }                    else if (a[u] > b[v]) {            //         qaq[++wt] = b[v];                     v++;                    }                    else {                        qaq[++wt] = a[u];                        u++; v++;                    }                }            }            vector<ygorz> c;            if(wt){                c.clear();                qaq[wt + 1].first = -1;                for (int i = 1; i <= wt; i++){                    c.push_back(qaq[i]);                }                }            st.push(c);        }        else {            ULL hash = 5;            int ll = 2;            vector<ygorz> a = st.top(); st.pop();            vector<ygorz> b = st.top(); st.pop();            for (int i = 0; i < a.size(); i++) {                hash = hash * power[a[i].second] + a[i].first;                ll += a[i].second;                ll %= 199193;            }            hash = hash * power[a.size()] + 7;            a.clear();            a.push_back(make_pair(hash, ll));            int u = 0, v = 0;            int wt = 0;            while (u < a.size() || v < b.size()) {                if (u == a.size()) {                    qaq[++wt] = b[v];                    v++;                }                else if (v == b.size()) {                    qaq[++wt] = a[u];                    u++;                }                else {                    if (a[u] < b[v]) {                        qaq[++wt] = a[u];                        u++;                    }                    else if (a[u] > b[v]) {                        qaq[++wt] = b[v];                        v++;                    }                    else {                        qaq[++wt] = a[u];                        u++; v++;                    }                }            }            vector<ygorz> c;            c.clear();            c.push_back(qaq[1]);            for (int i = 2; i <= wt; i++){                c.push_back(qaq[i]);            }            st.push(c);        }        printf("%d\n", st.top().size());    }    return 0;}

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