Summary Ranges

1. Title

Summary Ranges

2.   Http address

https://leetcode.com/problems/summary-ranges/

3. The question

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

For example, given [0,1,2,4,5,7], return ["0->2","4->5","7"].

4 My code(AC)

// Accepted
    public List<String> summaryRanges(int[] nums) {
        
        List<String> result = new ArrayList<String>();
        if ( nums == null || nums.length <=0)
            return result;        
        
        int len = nums.length;
        
        if( len == 1)
        {
            result.add(nums[0]+"");
            return result;
        }
        int beginIndex = 0;
        for(int i = 1; i < len ; i++)
        {
            if( nums[i] != nums[i-1] + 1)
            {
                if(beginIndex != i-1)
                {
                    result.add("" + nums[beginIndex] + "->" + nums[i-1]);
                }else{
                    result.add("" + nums[i-1]);
                }
                beginIndex = i;
            }
        }
        
        if(beginIndex != len-1)
        {
            result.add("" + nums[beginIndex] + "->" + nums[len-1]);
        }else{
            result.add("" + nums[len-1]);
        }
        return result;    
    }