Halfway to go, though I have finished 145 questions of leetcode online judge

It's quite a long way to go, step by step.

In my private opinion, there are 3 (or 4) steps to divide and 'conquer' Leetcode questions;

1st step, there might be about 50 easy questions, normally these 50 questions would take a bout 1 week to a student with ordinary knowledge of Java or C++ (LeetCode accepts Python recently).

2nd step, after solved 50 easy questions, here come about 50 slightly tough questions, these questions took me about 2 weeks to finish; 

3rd step, things went to be tougher after Q100, ==! I have to check other senior programmers' codes or algorithms, then write my own codes. During this phase, I could solve about 2 questions each day.

4th, after Question 140, the few questions left are top killers, I almost did not have any idea what on earth were these question asking me to do, ==!