23 Heap

L130 Hepify

378 Kth Smallest Element in a Sorted Matrix (L401)

L465 Kth Smallest Sum In Two Sorted Arrays -- 378的变体，用同样方法做

373 Find K Pairs with Smallest Sums -- 求所有解

L471 Top K Frequent Words -- 347 Top K Frequent Elements -- 692 Top K Frequent Words

L131 Building Outline （218 The Skyline Problem) --- sweep line，但用到了heap

L81 Data Stream Median (295 Find Median from Data Stream) -- also in coding interview & cc189 17.20

L360 Sliding Window Median -- 就是上一题加上窗口限制堆的大小

703 Kth Largest Element in a Stream -- 相关L5 Kth Largest Element （in array）用quick select

743 Network Delay Time

407 Trapping Rain Water II

1329 Sort the Matrix Diagonally

1675 Minimize Deviation in Array

1337 The K Weakest Rows in a Matrix