commit

Author: Bushraabir

219. Contains Duplicate II.cpp

@@ -0,0 +1,17 @@
+class Solution {
+public:
+    bool containsNearbyDuplicate(vector<int>& nums, int k) {
+        unordered_map<int, int> indexMap; 
+
+        for (int i = 0; i < nums.size(); i++) {
+            if (indexMap.find(nums[i]) != indexMap.end()) {
+                
+                if (i - indexMap[nums[i]] <= k)
+                    return true;
+            }
+            indexMap[nums[i]] = i; 
+        }
+
+        return false; 
+    }
+};

228. Summary Ranges.cpp

@@ -0,0 +1,35 @@
+class Solution {
+public:
+    vector<string> summaryRanges(vector<int>& nums) {
+        vector<string> res;
+        if (nums.empty()) return res;
+
+        int start = nums[0];   // start of current range
+        int end = nums[0];     // end of current range
+
+        for (int i = 1; i < nums.size(); ++i) {
+            if (nums[i] == end + 1) {
+               
+                end = nums[i];
+            } else {
+                
+                if (start == end) {
+                    res.push_back(to_string(start));
+                } else {
+                    res.push_back(to_string(start) + "->" + to_string(end));
+                }
+                
+                start = end = nums[i];
+            }
+        }
+
+      
+        if (start == end) {
+            res.push_back(to_string(start));
+        } else {
+            res.push_back(to_string(start) + "->" + to_string(end));
+        }
+
+        return res;
+    }
+};

268. Missing Number.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    void moveZeroes(vector<int>& nums) {
+        int j = 0;
+
+        for( int i = 0 ; i < nums.size() ; i++ ){
+
+            if( nums[i] != 0 ){
+                swap( nums[i] , nums[j] );
+                j++;
+            }
+        }
+
+
+    }
+};