Solved 3 problems

varunu28 · varunu28 · commit 340c491d8366 · 2017-12-03T21:01:48.000-08:00
diff --git a/Easy/Flood Fill.java b/Easy/Flood Fill.java
@@ -0,0 +1,20 @@
+class Solution {
+    public int[][] floodFill(int[][] image, int sr, int sc, int newColor) {
+        int color = image[sr][sc];
+        if (color != newColor) {
+            dfs(image, sr, sc, color, newColor);
+        }
+        
+        return image;
+    }
+    
+    public void dfs(int[][] image, int sr, int sc, int color, int newColor) {
+        if (image[sr][sc] == color) {
+            image[sr][sc] = newColor;
+            if (sr >= 1) dfs(image, sr-1, sc, color, newColor);
+            if (sc >= 1) dfs(image, sr, sc-1, color, newColor);
+            if (sr+1 < image.length) dfs(image, sr+1, sc, color, newColor);
+            if (sc+1 < image[0].length) dfs(image, sr, sc+1, color, newColor);
+        }
+    } 
+}
diff --git a/Easy/Longest Common Prefix.java b/Easy/Longest Common Prefix.java
@@ -0,0 +1,15 @@
+class Solution {
+    public String longestCommonPrefix(String[] strs) {
+        if (strs == null || strs.length == 0) return "";
+        
+        String ans = strs[0];
+        
+        for (int i=1;i<strs.length;i++) {
+            while(strs[i].indexOf(ans) != 0) {
+                ans = ans.substring(0,ans.length()-1);
+            }
+        }
+        
+        return ans;
+    }
+}
diff --git a/Easy/Repeated Substring Pattern.java b/Easy/Repeated Substring Pattern.java
@@ -0,0 +1,8 @@
+class Solution {
+    public boolean repeatedSubstringPattern(String s) {
+        String s1 = s + s;
+        String s2 = s1.substring(1,s1.length()-1);
+        
+        return s2.contains(s);
+    }
+}
