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

struct FenwickTree {
    vector<int> bit;// binary indexed tree
    int n;

    FenwickTree(int n) {
        this->n = n;
        bit.assign(n, 0);
    }

    FenwickTree(vector<int> a) : FenwickTree(a.size()) {
        for (size_t i = 0; i < a.size(); i++)
            add(i, a[i]);
    }

    int sum(int r) {
        int ret = 0;
        for (; r >= 0; r = (r & (r + 1)) - 1)
            ret += bit[r];
        return ret;
    }

    int sum(int l, int r) {
        return sum(r) - sum(l - 1);
    }

    void add(int idx, int delta) {
        for (; idx < n; idx = idx | (idx + 1))
            bit[idx] += delta;
    }
};


int main() {
    FenwickTree 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.add(results[who], -1);
            }
            results[who] = result;
            tree.add(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;
    }
}