Solved 3 problemds

varunu28 · varunu28 · commit 38ec921b57f1 · 2017-11-25T15:03:43.000-08:00
diff --git a/Medium/Battleships in a board.java b/Medium/Battleships in a board.java
@@ -0,0 +1,20 @@
+class Solution {
+    public int countBattleships(char[][] board) {
+        int n = board.length;
+        if (n == 0) return 0;
+        int m = board[0].length;
+        
+        int count = 0;
+        for (int i=0;i<n;i++) {
+            for (int j=0;j<m;j++) {
+                if (board[i][j] == '.') continue;
+                if (i > 0 && board[i-1][j] == 'X')continue;
+                if (j > 0 && board[i][j-1] == 'X')continue;
+                
+                count++;
+            }
+        }
+        
+        return count;
+    }
+}
diff --git a/Medium/Find Bottom Left Tree Value.java b/Medium/Find Bottom Left Tree Value.java
@@ -0,0 +1,27 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    int ans = 0;
+    int height = 0;
+    
+    public int findBottomLeftValue(TreeNode root) {
+        findBottomLeftValue(root, 1);
+        return ans;
+    }
+    
+    public void findBottomLeftValue(TreeNode root, int depth) {
+        if (height < depth) {
+            ans = root.val;
+            height = depth;
+        }
+        if (root.left!=null) findBottomLeftValue(root.left, depth+1);
+        if (root.right!=null) findBottomLeftValue(root.right, depth+1);
+    }
+}
diff --git a/Medium/Find Largest Value in Tree Row.java b/Medium/Find Largest Value in Tree Row.java
@@ -0,0 +1,55 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    
+    public List<Integer> largestValues(TreeNode root) {
+        
+        List<Integer> ans = new ArrayList<>();
+        
+        if (root == null) return ans;
+        
+        ArrayList<TreeNode> arr = new ArrayList<>();
+        arr.add(root);
+        
+        while (arr.size() != 0) {
+            ArrayList<TreeNode> roots = new ArrayList<>();
+            ArrayList<Integer> a = new ArrayList<>();
+            
+            int i = 0;
+            
+            while (i < arr.size()) {
+                TreeNode p = arr.get(i);
+                if (p.left != null) {
+                    roots.add(p.left);
+                }
+                if (p.right != null) {
+                    roots.add(p.right);
+                }
+                
+                a.add(p.val);
+                
+                i++;
+            }
+
+            Collections.sort(a);
+            
+            ans.add(a.get(a.size()-1));
+            arr.clear();
+            
+            i = 0;
+            while(i < roots.size()) {
+                arr.add(roots.get(i));
+                i++;
+            }
+        }
+        
+        return ans;
+    }
+}
