O(1) time vector rotateLeft(int d, vector arr) { vector result; int step = d % arr.size();

vector<int> left(arr.begin() + step, arr.end());
vector<int> right(arr.begin(), arr.begin() + step);
result.insert(result.end(), left.begin(), left.end());
result.insert(result.end(), right.begin(), right.end());

return result;

}