int twoRobots(int M, int N, vector<vector<int>> queries) {
    vector<vector<int>> cache(N, vector<int>(M+1, INT_MAX));
    set<int> endStates = {0};
    cache[0][0] = abs(queries[0][1] - queries[0][0]);
    for (int i=1; i < N; i++) {
        for (int x : endStates) cache[i][x] = cache[i-1][x] + abs(queries[i][0] - queries[i-1][1]) + abs(queries[i][1] - queries[i][0]);
        int temp = INT_MAX;
        for (int y : endStates) {
            if (y != 0) temp = min(temp, cache[i-1][y] + abs(queries[i][0] - y) + abs(queries[i][1] - queries[i][0]));
            else temp = min(temp, cache[i-1][y] + abs(queries[i][1] - queries[i][0]));
        }
        cache[i][queries[i-1][1]] = min(cache[i][queries[i-1][1]], temp);
        endStates.insert(queries[i-1][1]);
    }
    return *min_element(cache[N-1].begin(), cache[N-1].end());
}