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.
Code
class Solution {
public List<String> summaryRanges(int[] nums) {
List<String> result = new ArrayList<> ();
if (nums == null || nums.length == 0)
return result;
List<String> range = new ArrayList<> ();
int start = nums[0];
double end = Double.MAX_VALUE;
for (int i = 1; i < nums.length; i++) {
if (nums[i] == nums[i - 1] + 1) {
end = nums[i];
continue;
}
String endRange = end == Double.MAX_VALUE ? "" : "->" + (int) (end);
String entry = String.valueOf (start) + endRange;
range.add (entry);
start = nums[i];
end = Double.MAX_VALUE;
}
String endRange = end == Double.MAX_VALUE ? "" : "->" + (int)end;
String entry = String.valueOf (start) + endRange;
range.add (entry);
return range;
}
}
