[LeetCode] 228. Summary Ranges

轉自LeetCode

Given a sorted integer array without duplicates, return the summary of its ranges.

Example 1:

Input:  [0,1,2,4,5,7]
Output: ["0->2","4->5","7"]
Explanation: 0,1,2 form a continuous range; 4,5 form a continuous range.

Example 2:

Input:  [0,2,3,4,6,8,9]
Output: ["0","2->4","6","8->9"]
Explanation: 2,3,4 form a continuous range; 8,9 form a continuous range.

<Solution>

想法如下

• 因為是 sorted array，且沒有 duplicates，那麼如果是連續數字，則 index 的差值，就會等於 value 的差值

• 過程中，使用 binary search 的方式，來找到不是連續的數字

code 如下

Java(參考解法)