// Task: SAM

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main(){
    int n;

    cin >> n;

    vector<vector<int>> characteristics(2);

    for (auto v: characteristics) {
        v.reserve(n);
    }

    for (int i = 0; i < n; ++i) {
        int r, w, t;

        cin >> r >> w >> t;

        characteristics[r - 1].push_back(w - t);
    }

    for (int i = 0; i < characteristics.size(); ++i) {
        sort(characteristics[i].begin(), characteristics[i].end());
    }

    int toRemove = 0;

    vector<int>::iterator iterators[2];

    for (int i = 0; i < 2; ++i) {
        iterators[i] = characteristics[i].begin();
    }

    // Illustration
    // 1 1 2 3 3 3 4 5 6
    // 2 2 2 2 3 3 5 7 7

    while (iterators[0] != characteristics[0].end() &&
            iterators[1] != characteristics[1].end()) {
        if (*iterators[0] < *iterators[1]){
            ++iterators[0];

            continue;
        }
        if (*iterators[0] > *iterators[1]){
            ++iterators[1];

            continue;
        }

        const int COMMON_VALUE = *iterators[0];

        int collisions[2] = {0, 0};

        for (int i = 0; i < 2; ++i) {
            while ((iterators[i] != characteristics[i].end()) &&
                *iterators[i] == COMMON_VALUE){
                ++collisions[i];
                ++iterators[i];
            }
        }

        toRemove += min(collisions[0], collisions[1]);
    }

    cout << toRemove << endl;

    return 0;
}