昨日のD https://codeforces.com/contest/1348/problem/D 隙間時間に虚無埋め https://onlinejudge.u-aizu.ac.jp/challenges/sources/JOI/Prelim/0554 https://onlinejudge.u-aizu.ac.jp/challenges/sources/JOI/Prelim/0565 https://onlinejudge.u-aizu.ac.…