228. Summary Ranges

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"].

Solution 1 straightforward way
1ms 3.27%
public class Solution {
public List<String> summaryRanges(int[] nums) {
List<String> list = new ArrayList<String>();
int start = 0;
for(int i = 0; i < nums.length; i++){
if((i + 1) == nums.length){
String s;
if((i - start) == 0){
s = nums[i] + "";
}else{
s = nums[start] + "->" + nums[i];
}
list.add(s);
break;
}
if(nums[i + 1] != nums[i] + 1){
String s;
if(i == start){
s = nums[i] + "";
}else{
s = nums[start] + "->" + nums[i];
}
list.add(s);
start = i + 1;
}
}
return list;
}
}

Didn't find any better solution except using StringBuilder.