package leetcode;

/*

* 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 [“2”, “4->49”, “51->74”, “76->99”]*/

import java.util.ArrayList;

import java.util.List;

public class MissingRange {

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

List<String> ret = new ArrayList<String>();

int prev = lower-1;

for(int num:nums){

if(num - prev > 1){

ret.add(this.addRange(prev+1, num-1));

}

prev = num;

}

if(nums.length > 0 && nums[nums.length-1] != upper){

ret.add(this.addRange(nums[nums.length-1]+1, upper));

}

if(nums.length == 0){

ret.add(this.addRange(lower,upper));

}

return ret;

}

private String addRange(int start,int end){

if(start == end)

return Integer.toString(start);

else

return Integer.toString(start) + "->" + Integer.toString(end);

}

}