摘要：这类问题可以先用递归思考，再反过来想出动态规划的方法。 10. Regular Expression Matching 32. Longest Valid Parentheses 44. Wildcard Matching 72. Edit Distance 97. Interleaving Str 阅读全文

摘要：121. Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitte 阅读全文

摘要：lo和hi都是inclusive的。 返回的数组中，index小于j的数都小于等于j，index大于j的数都大于等于j 阅读全文

摘要：procedure three-way-partition(A : array of values, mid : value): i ← 0 j ← 0 n ← size of A - 1 while j ≤ n: if A[j] < mid: swap A[i] and A[j] i ← i + 阅读全文

摘要： 阅读全文

摘要：很开心，自己想出来的一道题 There is a list of sorted integers from 1 to n. Starting from left to right, remove the first number and every other number afterward un 阅读全文