#include <unordered_map>
#include <queue>

/*
    Task scheduling with changeable priorities
*/

class PriorityManager {
private:
    std::unordered_map<int, int> info;
    std::priority_queue<std::pair<int, int>> heap;
public:
    PriorityManager(std::vector<std::pair<int, int>>& tasks) {
        for (auto& task : tasks) {
            int taskId = task.first, priority = task.second;
            info[taskId] = priority;
            heap.push(std::make_pair(priority, taskId));
        }
    }

    void add(int taskId, int priority) {
        info[taskId] = priority;
        heap.push(std::make_pair(priority, taskId));
    }

    void edit(int taskId, int newPriority) {
        info[taskId] = newPriority;
        heap.push(std::make_pair(newPriority, taskId));
    }

    void rmv(int taskId) {
        info.erase(taskId);
    }

    int execTop() {
        while (!heap.empty()) {
            auto task = heap.top();
            heap.pop();
            int priority = task.first, taskId = task.second;

            if (info.find(taskId) != info.end() && info[taskId] == priority) {            
                rmv(taskId);
                return taskId;
            }
        }
        return -1;
    }
};