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+Longest Consecutive Subsequence...
+
+Given an array of integers, find the length of the longest sub-sequence such that
+elements in the subsequence are consecutive integers,
+the consecutive numbers can be in any order.
+
+Examples--
+
+Input: arr[] = {1, 9, 3, 10, 4, 20, 2};
+Output: 4
+The subsequence 1, 3, 4, 2 is the longest subsequence
+of consecutive elements
+
+Input: arr[] = {36, 41, 56, 35, 44, 33, 34, 92, 43, 32, 42}
+Output: 5
+The subsequence 36, 35, 33, 34, 32 is the longest subsequence
+of consecutive elements.