Leetcode is a very nice platform to practice algorithms. unlike most of its peers, it provides insights about the runtime and memory used by the algorithm.

Leetcode has one weekly contest and one biweekly contest.

Solutions are provided in c++ and easily convertible into other languages.

Algorithms will be divided in the following categories, with between brackets the usual difficulty:

• Vector (easy to medium)
• String (easy to medium)
• Dynamic Programming (medium to hard)
• Subarray (medium to hard)
• Bit Manipulation (easy to hard)

could originally speed up with:

static int lambda_0 = []() { std::ios::sync_with_stdio(false); cin.tie(null); return 0; }();

nb: (for myself) to write an n superscript digit (power of) use following unicode:

ctrl+shift+u and then if n = 3 'b3', if n = 2 'b2', if n = 1 'b9'
ctrl+shift+u and then '2' '0' '7' and ending with n for other digits