new

Author: Yubin Bai

.gitignore

@@ -61,4 +61,7 @@ out/
 
 # Maven
 log/
-target/
+target/
+
+#sublime
+*.sublime-workspace

README.md

@@ -3,6 +3,7 @@ Leetcode solutions in Java and Python
 
 |#|Title|Solution|Difficulty|
 |---|-----|--------|----------|
+|228|[Summary Ranges](https://leetcode.com/problems/summary-ranges/)|[Java](./src/summary_ranges)|Easy|
 |227|[Basic Calculator II](https://leetcode.com/problems/basic-calculator-ii/)|[Java](./src/basic_calculator_ii)|Medium|
 |226|[Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/)|[Java](./src/invert_binary_tree)|Easy|
 |225|[Implement Stack using Queues](https://leetcode.com/problems/implement-stack-using-queues/)|[Java](./src/implement_stack_using_queues)|Medium|

leetcode.sublime-project

@@ -0,0 +1,18 @@
+{
+	"folders":
+	[
+		{
+			"path": "."
+		}
+	],
+	"build_systems":
+	[
+		{
+			"name": "Run",
+			"cmd": ["javac \"$file_name\" && java \"$file_base_name\""],
+			"shell": true,
+			"file_regex": "^(...*?):([0-9]*):?([0-9]*)",
+			"selector": "source.java"
+		}
+	]
+}

src/summary_ranges/README.md

@@ -0,0 +1,6 @@
+Problem
+===
+
+Given a sorted integer array without duplicates, return the summary of its ranges.
+
+For example, given [0,1,2,4,5,7], return ["0->2","4->5","7"].

src/summary_ranges/Solution.java

@@ -0,0 +1,34 @@
+import java.util.*;
+
+public class Solution {
+    public List<String> summaryRanges(int[] nums) {
+        List<String> list = new ArrayList<String>();
+        if (nums.length == 0) return list;
+        int prev = nums[0];       
+        int curr = prev;
+        for (int i = 1; i < nums.length; i++) {
+            if (nums[i] == curr + 1) {
+                curr++;
+            } else {
+                if (prev == curr) {
+                    list.add(String.format("%d", prev));
+                } else {
+                    list.add(String.format("%d->%d", prev, curr));
+                }
+                prev = nums[i];
+                curr = nums[i];
+            }
+        }
+        if (prev == curr) {
+            list.add(String.format("%d", prev));
+        } else {
+            list.add(String.format("%d->%d", prev, curr));
+        }
+        return list;
+    }
+    public static void main(String[] args) {
+        int[] nums = new int[] {0,1,2,4,5,7};
+        Solution s = new Solution();
+        s.summaryRanges(nums).forEach(System.out::println);
+    }
+}