Create 448_find_all_numbers_disappeared_in_an_array.cpp

Author: Rashed112

solutions/448_find_all_numbers_disappeared_in_an_array.cpp

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+//Solution-1
+//Time: O(n), Space: O(n)
+class Solution {
+public:
+    vector<int> findDisappearedNumbers(vector<int>& nums) {
+        unordered_map<int, int>ump;
+        vector<int>res;
+        for(int i=0;i<nums.size();i++){
+            ump[nums[i]]++;
+        }
+        for(int i=1;i<=nums.size();i++){
+            if(ump.find(i) == ump.end()){
+                res.push_back(i);
+            }
+        }
+        return res;
+    }
+};
+//Solution-2
+//Time: O(n), Space: O(1)
+class Solution {
+public:
+    vector<int> findDisappearedNumbers(vector<int>& nums) {
+        vector<int>res;
+        for(int i=0;i<nums.size();i++){
+            nums[abs(nums[i])-1] = - abs(nums[abs(nums[i])-1]);
+        }
+        for(int i=0;i<nums.size();i++){
+            if(nums[i]>0){
+                res.push_back(i+1);
+            }
+        }
+        return res;
+    }
+};