摘要：
D. Sum in the tree time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Mitya has a rooted tr 阅读全文
摘要：
C. Postcard time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Andrey received a postcard fr 阅读全文
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B. Squares and Segments time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Little Sofia is i 阅读全文
摘要：
A. Snowball time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Today's morning was exception 阅读全文