CP Editor is designed for competitive programming. It helps you focus on your algorithms and automates the compilation, execution and testing of your code. It can fetch test cases from different platforms and submit solutions to Codeforces. It automates all that's reasonably possible and allows you to purely focus on your code. Say no to manual efforts of running and testing your code against expected outputs.
...Enabling you to switch between input styles makes Spacemacs a great choice for pair-programming.
Spacemacs features a beautiful GUI and exceptional ergonomics, with all the key bindings easily accessible simply by pressing the space bar or alt-m. Spacemacs also comes with hundreds of curated, ready-to-use packages that are well organised in configuration layers.