Two-Pointers-1 Done

3SumProblem.java

@@ -0,0 +1,33 @@
+class Solution {
+    public List<List<Integer>> threeSum(int[] nums) {
+        Arrays.sort(nums);
+        List<List<Integer>> result = new ArrayList<>();
+        List<Integer> list = new ArrayList<>();
+        for(int i=0;i<nums.length-2;++i){
+            if(i!=0 && nums[i]==nums[i-1]) continue;
+            if(nums[i]>0) continue;
+            int target = nums[i];
+            int left = i+1;
+            int right = nums.length-1;
+            while(left<right){
+                int sum = nums[left]+nums[right]+target;
+                if(sum==0){
+                    result.add(Arrays.asList(nums[left],nums[right],target));
+                    left++;
+                    right--;
+                    while(left<right && nums[left]==nums[left-1]){
+                        left++;
+                    }
+                    while(left<right && nums[right]==nums[right+1]){
+                        right--;
+                    }
+                }else if(sum>0){
+                    right--;
+                }else{
+                    left++;
+                }
+            }
+        }
+        return result;
+    }
+}

ContainerWaterProblem.java

@@ -0,0 +1,19 @@
+class Solution {
+    public int maxArea(int[] height) {
+       int left = 0;
+       int right = height.length-1;
+       int max = 0;
+       while(left<right){
+            int width = right-left;
+            int heightOfLines = Math.min(height[left],height[right]);
+            int area = width * heightOfLines;
+            max = Math.max(max,area);
+            if(height[left]<height[right]){
+                left++;
+            }else{
+                right--;
+            }
+       } 
+       return max;
+    }
+}

Sample.java

@@ -4,4 +4,29 @@
 // Any problem you faced while coding this :
 
 
-// Your code here along with comments explaining your approach
+// Your code here along with comments explaining your approach
+
+class Solution {
+    public void sortColors(int[] nums) {
+       if(nums.length==1) return; 
+       int i = 0;
+       int mid = 0;
+       int k = nums.length-1;
+       while(mid<=k){
+          if(nums[mid]==2){
+             swap(nums,mid,k);
+             k--;
+          }else if(nums[mid]==0){
+             swap(nums,mid,i);
+             i++; mid++;
+          }else{
+             mid++;
+          }
+       } 
+    }
+    void swap(int[] nums,int i,int j){
+        int temp = nums[i];
+        nums[i] = nums[j];
+        nums[j] = temp;
+    }
+}