66import java .util .List ;
77import java .util .Map ;
88
9- /**
10- * 1228. Missing Number In Arithmetic Progression
11- *
12- * In some array arr, the values were in arithmetic progression: the values arr[i+1] - arr[i] are all equal for every 0 <= i < arr.length - 1.
13- * Then, a value from arr was removed that was not the first or last value in the array.
14- * Return the removed value.
15- *
16- * Example 1:
17- * Input: arr = [5,7,11,13]
18- * Output: 9
19- * Explanation: The previous array was [5,7,9,11,13].
20- *
21- * Example 2:
22- * Input: arr = [15,13,12]
23- * Output: 14
24- * Explanation: The previous array was [15,14,13,12].
25- *
26- * Constraints:
27- * 3 <= arr.length <= 1000
28- * 0 <= arr[i] <= 10^5
29- * */
309public class _1228 {
3110public static class Solution1 {
32- /**A super verbose and inefficient but working way...*/
11+ /**
12+ * A super verbose and inefficient but working way...
13+ */
3314public int missingNumber (int []arr ) {
3415Arrays .sort (arr );
3516Map <Integer ,List <Integer >>map =new HashMap <>();
@@ -50,7 +31,9 @@ public int missingNumber(int[] arr) {
5031 }
5132
5233public static class Solution2 {
53- /**credit: https://leetcode.com/problems/missing-number-in-arithmetic-progression/discuss/408474/JavaC%2B%2BPython-Arithmetic-Sum-and-Binary-Search*/
34+ /**
35+ * credit: https://leetcode.com/problems/missing-number-in-arithmetic-progression/discuss/408474/JavaC%2B%2BPython-Arithmetic-Sum-and-Binary-Search
36+ */
5437public int missingNumber (int []arr ) {
5538int min =arr [0 ];
5639int max =arr [0 ];