163. Missing Ranges
Given a sorted integer array where the range of elements are [0, 99] inclusive, return its missing ranges.
For example, given [0, 1, 3, 50, 75], return [“2â€, “4->49â€, “51->74â€, “76->99â€]
//https://discuss.leetcode.com/topic/10681/my-concise-java-accepted-solution
public class Solution {
public List findMissingRanges(int[] A, int lower, int upper) {
List result = new ArrayList();
int pre = lower - 1;
for(int i = 0 ; i <= A.length; i++){
int after = i == A.length ? upper + 1 : A[i];
if(pre + 2 == after){
result.add(String.valueOf(pre + 1));
}else if(pre + 2 < after){
result.add(String.valueOf(pre + 1) + "->" + String.valueOf(after - 1));
}
pre = after;
}
return result;
}
}
//////////////////////////////////////
public class Solution {
public List findMissingRanges(int[] nums, int lower, int upper) {
List res = new LinkedList();
int l = lower;
for (int i = 0; i <= nums.size(); ++i) {
int r = (i < nums.length && nums[i] <= upper) ? nums[i] : upper + 1;
if (l == r) {
++l;
} else if (r > l) {
res.add(r-l == 1 ? String.valueOf(l) : String.valueOf(l) + "->" + String.valueOf(r - 1));
l = r + 1;
}
}
return res;
}
}