紫书第五章习题 5-14 UVa1598-Exchange

出处：https://blog.youkuaiyun.com/zju2016/article/details/75005098

题目链接：https://vjudge.net/contest/231030#problem/N

    #include<iostream>  
    #include<vector>  
    #include<string>  
    #include<type_traits>  
    #include<sstream>  
    #include<tuple>  
    #include<bitset>  
    #include<regex>  
    #include<set>  
    #include<stack>  
    #include<queue>  
    #include<map>  
    #include<algorithm>  
    using namespace std;  
      
    map<int, set<int>> Buy;//映射：购买价格到购买的指令编号  
    map<int, int> Buy_total;//映射：购买价格到购买总量  
    map<int, set<int>> Sell;//映射：卖的价格到卖的指令编号  
    map<int, int> Sell_total;//映射：贩卖价格到贩卖总量  
    typedef struct command{  
        string com;  
        int price, amount;  
        int id;  
    }command;  
      
    vector<command> Com;//存储指令  
      
    void Deal(int flag){//处理"TRADE"  
        while (!Buy.empty()&&!Sell.empty()){  
            if (Buy.rbegin()->first>=Sell.begin()->first){  
                set<int>& v1 = Buy.rbegin()->second;  
                set<int>& v2 = Sell.begin()->second;  
                int number1 = *v1.begin();  
                int number2 = *v2.begin();  
                int size = min(Com[number1].amount,Com[number2].amount);  
                Com[number1].amount -= size;  
                Com[number2].amount -= size;  
                Buy_total[Com[number1].price] -= size;  
                Sell_total[Com[number2].price] -= size;  
                cout << "TRADE " << size << " " << (flag ? Com[number1].price : Com[number2].price)<<endl;  
                if (Com[number1].amount == 0) v1.erase(number1);  
                if (Com[number2].amount == 0) v2.erase(number2);  
                if (Buy_total[Com[number1].price] == 0) Buy_total.erase(Com[number1].price);  
                if (Sell_total[Com[number2].price] == 0) Sell_total.erase(Com[number2].price);  
                if (v1.size() == 0) Buy.erase(Com[number1].price);  
                if (v2.size() == 0) Sell.erase(Com[number2].price);  
            }  
            else{  
                return;  
            }  
        }  
    }  
      
    void Print(){//处理"QUOTE"  
        cout << "QUOTE ";  
        if (Buy_total.size() == 0) cout << "0 0 - ";  
        else{  
            cout<<Buy_total.rbegin()->second<<  " " <<  Buy_total.rbegin()->first << " - ";  
        }  
        if (Sell_total.size() == 0) cout << "0 99999" << endl;  
        else cout <<Sell_total.begin()->second << " " << Sell_total.begin()->first <<  endl;  
    }  
      
    int main(){  
        int Case = 0;  
        int n;  
        while (cin >> n){  
            Buy.clear();  Buy_total.clear();  
            Sell.clear(); Sell_total.clear();  
            Com.clear();  
            if (Case++) cout << endl;  
            for (int i = 0; i < n; i++){  
                command temp;  
                cin >> temp.com;  
                if (temp.com == "BUY"){  
                    cin >> temp.amount >> temp.price;  
                    Buy[temp.price].insert(i);  
                    Buy_total[temp.price] += temp.amount;  
                    Com.push_back(temp);  
                    Deal(0);  
                }  
                else if (temp.com=="SELL"){  
                    cin >> temp.amount >> temp.price;  
                    Sell[temp.price].insert(i);  
                    Sell_total[temp.price] += temp.amount;  
                    Com.push_back(temp);  
                    Deal(1);  
                }  
                else{  
                    int id;  
                    cin >> id;  
                    id--;  
                    temp.id = id;  
                    Com.push_back(temp);  
                    int price = Com[id].price;  
                    if (Com[id].com == "BUY"){  
                        Buy[price].erase(id);  
                        Buy_total[price] -= Com[id].amount;  
                        if (Buy[price].empty()) Buy.erase(price);  
                        if (Buy_total[price] == 0) Buy_total.erase(price);  
                        Com[id].amount = 0;  
                    }  
                    if(Com[id].com=="SELL"){  
                        Sell[price].erase(id);  
                        Sell_total[price] -= Com[id].amount;  
                        if (Sell[price].empty()) Sell.erase(price);  
                        if (Sell_total[price] == 0) Sell_total.erase(price);  
                        Com[id].amount = 0;  
                    }  
                }  
                Print();  
            }  
        }  
        return 0;  
    }