Before I decided to set data science as my career goal, I was a Physics PhD who did a lot of tool operations and optical measurements in semiconducting field. Coding was not a daily work for me. Here I introduced a little about my background to encourage people with a similar background or just as new learners in coding. Before learning data structure, I have known some basic knowledge about Matlab and C. I used Matlab to visualize two-dimensional electronic signal in the experiments. When freshman at Nanjing University, I had a really bad experience of learning C langurange and wasted a lot of time just debuging the synatax. Anyway, I was new to data structure before 2017 spring.