#include <iostream>
#include <vector>
#include <map>

int main() {
    int n;
    std::cin >> n;
    int maxT = 0;
    int result = 0;
    std::vector<std::pair<int, int> > firstType, secondType;
    std::map<int, int> firstTypeMap, secondTypeMap;
    for (int i = 0; i < n; i++) {
        int r, w, t;
        std::cin >> r >> w >> t;
        if (t > maxT) {
            maxT = t;
        }
        if (r == 1) {
            firstType.emplace_back(w, t);
        } else {
            secondType.emplace_back(w, t);
        }
    }

    for (auto p : firstType) {
        firstTypeMap[p.first - p.second - maxT]++;
    }
    for (auto p : secondType) {
        secondTypeMap[p.first - p.second - maxT]++;
    }

    for (const auto &p : firstTypeMap) {
        if (secondTypeMap[p.first] > 0) {
            result += std::min(p.second, secondTypeMap[p.first]);
        }
    }

    std::cout << result;
    return 0;
}