Four new practice sets, from Easy 100 to segment trees
AtCoder’s Boot camp Easy 100, CSES Range Queries, the AtCoder Library Practice Contest and AtCoder’s Let’s use segtree! contest.
What changed
Four published problem lists joined the CSES and AtCoder workspaces, each in its original order.
Every row links to an English statement on the judge and carries a one-line approach and topic. Each set ends in a boss. If you link your AtCoder handle, solves on the three AtCoder lists sync on their own; you mark CSES solves yourself.
Boot camp for Beginners: Easy 100, 100 tasks from AtCoder Problems, listed after Beginners Selection.
CSES Range Queries: all 25 tasks, in five steps.
AtCoder Library Practice Contest: 12 tasks.
AAL Contest 001: Let’s use segtree!, AtCoder’s 24-task segment tree contest from October 12, 2026.
Try it
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