LeetCode - 228. Summary Ranges - 返回vector的联通分段

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.

思路：

    一张图证明这题有多简单 = =。

    AC代码如下：

vector summaryRanges(vector& nums)
{
    int len = nums.size();
    vector res;
    if(len == 0)
        return res;
    int i = 0;
    while(i < len)
    {
        int t = 1;
        while(nums[i + t] - nums[i] == t)
            ++t;
        --t;
        if(t == 0)  // 单独
        {
            res.push_back(to_string(nums[i]));
            ++i;
        }
        else        // 连续
        {
            string tmp = to_string(nums[i]);
            tmp += ("->");
            tmp += to_string(nums[i + t]);
            res.push_back(tmp);
            i += (t + 1);
        }
    }
    return res;
}