Problems from AtCoder and Codeforces are both fine, preferably those where the 'Exchange arguments' method is used to optimize greedy algorithms.
Thanks~
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Problems from AtCoder and Codeforces are both fine, preferably those where the 'Exchange arguments' method is used to optimize greedy algorithms.
Thanks~
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https://codeforces.me/problemset/problem/1793/E
https://codeforces.me/contest/1914/problem/E2
https://oj.uz/problem/view/NOI22_gymbadges
Exchange arguments is not an optimisation technique? It's a proving method not an algorithm or technique. In any case, a problem which can be proved using this method. https://codeforces.me/problemset/problem/632/C
You can refer to this blog: https://codeforces.me/blog/entry/63533