Longest Consecutive Sequence

Author: alisamad1

arrays/longest_consecutive_sequence.cpp

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+#include<iostream>
+#include<unordered_map>
+#include<vector>
+using namespace std;
+int longestconsecutiveSeq(vector<int>& nums){
+    unordered_map<int, bool> mp;
+    for(int i = 0; i < nums.size(); i++){
+        mp[nums[i]] = true;
+    }
+    for(int i = 0; i < nums.size(); i++){
+        if(mp.find(nums[i] - 1) != mp.end()){
+            mp[nums[i]] = false;
+        }
+    }
+    int maxLen = 0;
+    for(int i = 0; i < nums.size(); i++){
+        if(mp[nums[i]]){
+            int j = 0;
+            int count = 0;
+            while(mp.count(nums[i] + j) > 0){
+                j++;
+                count++;
+            }
+            if(count > maxLen){
+                maxLen = count;
+            }
+        }
+    }
+    return maxLen;
+}
+int main(){
+    int n;
+    cout << "Enter the number of elements in the array: ";
+    cin >> n;
+    vector<int> nums(n);
+    cout << "Enter the elements of the array: ";
+    for(int i = 0; i < n; i++){
+        cin >> nums[i];
+    }
+    int result = longestconsecutiveSeq(nums);
+    cout << "Length of the longest consecutive sequence: " << result << endl;
+    return 0;
+}