void solve() {
    int n, m; cin >> n >> m;
    vector<pair<int, int> > v; v.reserve(n * m);
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            v[m * (i - 1) + j - 1] = {i, j};
        }
    }
    bool low = true;
    int l = 0, r = m * n - 1;
    while (r >= l) {
        pair<int, int> u;
        if (low) {
            u = v[l]; l++;
            low = false;
        }
        else {
            u = v[r]; r--;
            low = true;
        }
        cout << u.first << " " << u.second << endl;
    }
}

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