https://leetcode.com/problems/maximize-happiness-of-selected-children/description/

Sum of k maximums decreasing each step #medium #sorting #heap #quickselect

https://leetcode.com/problems/kth-largest-sum-in-a-binary-tree/description/

`k`th largest level-sum in a tree #bfs #heap #quickselect

Min sum of differences of x times #medium #math #quickselect



https://leetcode.com/problems/minimum-operations-to-make-a-uni-value-grid/description/