// Given a sorted integer array where the range of elements are in the inclusive range [lower, upper], return its missing ranges.

// For example, given [0, 1, 3, 50, 75], lower = 0 and upper = 99, return ["2", "4->49", "51->74", "76->99"].

public class Solution {

public List<String> findMissingRanges(int[] nums, int lower, int upper) {

ArrayList<String> result = new ArrayList<String>();

for(int i = 0; i <= nums.length; i++) {

long start = i == 0 ? lower : (long)nums[i - 1] + 1;

long end = i == nums.length ? upper : (long)nums[i] - 1;

addMissing(result, start, end);

}

return result;

}

void addMissing(ArrayList<String> result, long start, long end) {

if(start > end) {

return;

}

else if(start == end) {

result.add(start + "");

}

else {

result.add(start + "->" + end);

}

}

}