228.Summary Ranges

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.

class Solution {
    public List<String> summaryRanges(int[] nums) {
        List<String> list=new ArrayList<>();
        if(nums.length == 1){
            list.add(nums[0] + "");
            return list;
        }
        for(int i = 0; i < nums.length; i++) {
            int a = nums[i];
            while(i + 1 < nums.length && (nums[i + 1] - nums[i]) == 1){
                i++;
            }
            if(a != nums[i]){
                list.add(a + "->" + nums[i]);
            } else {
                list.add(a + "");
            }
        }
        return list;
    }
}