Don't sit down in front of your computer until you have a very good idea of how your algorithm is going to work and how to code it. Sit down in front of a piec

Don't sit down in front of your computer until you have a very good idea of how your algorithm is going to work and how to code it. Sit down in front of a piece of paper with a pen. Draw diagrams to visualize the data structures that you're working with. Sketch different corner cases (for example, arrays of odd and even length). Informally (playfully) derive an algorithm to do what you want and convince yourself that it does what you want. Play through different cases on paper, maybe use markers (coins) to keep track of where you are. Write down the details so you don't have to keep them in your head. I have plenty of experience now, but I still use paper and pencil when I have to solve a problem I haven't solved before. It's just so much easier to explore the problem on paper, to think about corner cases, to visualize the inputs, outputs, and intermediate data structures, and to wrap your head around everything.