check_if_n_and_its_double_exist.cpp

Author: geeky01adarsh

README.md

@@ -4,6 +4,6 @@
 
 | S.No. | Topic | Status |
 |---|--------------|-----|
-|01. | [Array](https://github.com/geeky01adarsh/DSA-Interview-Questions/tree/main/Arrays) | 24/28 |
-|02. | [Searching](/Searching)|14/38|
+|01. | [Array](/Arrays) | 24/28 |
+|02. | [Searching](/Searching)|15/38|
 |03. | [Sorting](/Sorting)|0/38|

Searching/README.md

@@ -16,7 +16,7 @@
 |11| [Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/)|[Solution](intersection_of_two_arrays_i.cpp)|
 |12| [Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/)|[Solution](intersection_of_two_arrays_ii.cpp)|
 |13| [Fair Candy Swap](https://leetcode.com/problems/fair-candy-swap/)|Pending|
-|14| [Check If N and Its Double Exist](https://leetcode.com/problems/check-if-n-and-its-double-exist/)|Pending|
+|14| [Check If N and Its Double Exist](https://leetcode.com/problems/check-if-n-and-its-double-exist/)|[Solution](check_if_n_and_its_double_exist.cpp)|
 |15| [Special Array With X Elements Greater Than or Equal X](https://leetcode.com/problems/special-array-with-x-elements-greater-than-or-equal-x/)|Pending|
 |16| [Binary Search](https://leetcode.com/problems/binary-search/)|[Solution](binary_search.cpp)|
 |17| [Guess Number Higher or Lower](https://leetcode.com/problems/guess-number-higher-or-lower/)|[Solution](guess_no_higher_lower.cpp)|

Searching/check_if_n_and_its_double_exist.cpp

@@ -0,0 +1,31 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+bool checkIfExist(vector<int> &arr)
+{
+    unordered_map<int, int> map;
+    for (int i = 0; i < arr.size(); i++)
+    {
+        map[arr[i]]++;
+        if (arr[i] == 0 && map[arr[i]] == 1)
+            continue;
+        if (map.count(2 * arr[i]) > 0 || ((arr[i] % 2 == 0) && map.count(arr[i] / 2) > 0))
+            return true;
+    }
+    return false;
+}
+
+int main()
+{
+    int n;
+    cin >> n;
+    vector<int> v;
+    for (int i = 0; i < n; i++)
+    {
+        int temp;
+        cin >> temp;
+        v.push_back(temp);
+    }
+    cout << checkIfExist(v) << endl;
+    return 0;
+}