Added (LEETCODE) Longest Consecutive Sequence.cpp in Arrays

Author: gourangi-taware

Arrays/(LEETCODE) Longest Consecutive Sequence.cpp

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+// Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.
+
+// You must write an algorithm that runs in O(n) time.
+
+ 
+
+// Example 1:
+
+// Input: nums = [100,4,200,1,3,2]
+// Output: 4
+// Explanation: The longest consecutive elements sequence is [1, 2, 3, 4]. Therefore its length is 4.
+// Example 2:
+
+// Input: nums = [0,3,7,2,5,8,4,6,0,1]
+// Output: 9
+ 
+
+// Constraints:
+
+// 0 <= nums.length <= 105
+// -109 <= nums[i] <= 109
+
+// My Solution:
+
+class Solution {
+public:
+    int longestConsecutive(vector<int>& nums) {
+        if(nums.size() == 0)
+            return 0;
+        sort(nums.begin(), nums.end());
+        
+        int cus = 1;
+        int maxs = 1;
+        
+        for(int i=1;i<nums.size();i++){
+            if(nums[i]!=nums[i-1]){
+                if(nums[i] == nums[i-1]+1){
+                    cus+=1;
+            }
+            else{
+                maxs = max(maxs,cus);
+                cus = 1;
+            }
+        }
+       }
+        return max(maxs,cus);
+    }
+};