#include <iostream>
#include <unordered_map>
#include <vector>
#include <iomanip>
using namespace std;

class Fenwick {
public:
    Fenwick(int n) : size_(n), tree_(n){}

    Fenwick(vector<int> a) : Fenwick(a.size()) {
        for (size_t index = 0; index < a.size(); index++) {
            increment(index, a[index]);
        }
    }

    int sum(int right) {
        int s = 0;
        for (; right >= 0; right = (right & (right + 1)) - 1) {
            s += tree_[right];
        }
        return s;
    }

    void increment(int index, int delta) {
        for (; index < size_; index |= (index + 1))
            tree_[index] += delta;
    }

private:
    vector<int> tree_;
    int size_;
};


int main() {
    Fenwick tree(43000);
    int q;
    std::cin >> q;
    std::unordered_map<int, int> results;
    int amount = 0;
    while (q > 0) {
        std::string command;
        std::cin >> command;
        if (command == "RUN") {
            int who, result;
            std::cin >> who >> result;
            if (results.count(who) == 0) {
                ++amount;
            } else {
                tree.increment(results[who], -1);
            }
            results[who] = result;
            tree.increment(results[who], 1);
        } else {
            int who;
            std::cin >> who;
            if (results.count(who) == 0) {
                std::cout << 0 << "\n";
            } else if (amount == 1) {
                std::cout << 1 << "\n";
            } else {
                int a = tree.sum(results[who] - 1);
                std::cout << std::setprecision(6) << static_cast<double>(a) / (amount - 1) << "\n";
            }
        }
        --q;
    }
}