<ul>
<li>The problem of the form of the first and second moves against each other.</li>
<li>Attributing to <a href="/en/Nim">Nim</a> or using <a href="/en/Grundy%20number">Grundy number</a> are well-known solutions, but of course the problem is not simply attributed, but twisted.</li>
</ul>
<a href="https://algo-logic.info/combinatorial-games/">Fundamentals of combinatorial game theory and algorithms for determining winners and losers in Grundy numbers | Algorithmic Logic</a>
<ul>
<li><a href="/en/(playing)%20an%20unbiased%20game%20(unbiassed)">(playing) an unbiased game (unbiassed)</a></li>
</ul>
<a href="https://atcoder.jp/contests/arc038/tasks/arc038_d?lang=ja">D - Directed Graphs and Numbers</a> <a href="/en/arc038_d">arc038_d</a>
<a href="https://atcoder.jp/contests/arc046/tasks/arc046_b?lang=ja">B - Operation Stone Removal</a> <a href="/en/arc046_b">arc046_b</a>
<a href="https://atcoder.jp/contests/dp/tasks/dp_l?lang=ja">L - Deque</a> <a href="/en/DP%20L">DP L</a>
<a href="https://atcoder.jp/contests/dp/tasks/dp_k?lang=ja">K - Stones</a> <a href="/en/DP_K">DP_K</a>
<a href="https://atcoder.jp/contests/arc064/tasks/arc064_b?lang=ja">D - An Ordinary Game</a> <a href="/en/arc064_b">arc064_b</a>
<a href="https://atcoder.jp/contests/tkppc4-2/tasks/tkppc4_2_c">C - Parity</a> <a href="/en/tkppc4_2_c">tkppc4_2_c</a>
<a href="https://atcoder.jp/contests/arc038/tasks/arc038_b?lang=ja">B - squares and pieces</a> <a href="/en/arc038_b">arc038_b</a>
<a href="https://www.hamayanhamayan.com/entry/2017/02/27/025050">Summary of game problems in competitive programming Nim, Grundy numbers, regression analysis, minimax method - Hamayan Hamayan Hamayan</a>
<ul>
<li>ARC 013 C. Can you make me laugh?</li>
<li>AGC017 Game on Tree Description</li>
<li>ARC087 Prefix-free Game Description</li>
<li>ARC091 Strange Nim Description1 Description2</li>
<li>ARC 038 C. Teacups and beans</li>
<li>ARC038 Directed Graphs and Numbers Description</li>
<li>AGC020 Move and Win Description</li>
<li>EDPC Deque Description</li>
<li>ARC085 ABS Description</li>
</ul>
interactive
<ul>
<li><a href="https://atcoder.jp/contests/xmascon18/tasks/xmascon18_g">G - Good Game</a></li>
</ul>
<hr>
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competitive problem