diff --git a/solutions/228. Summary Ranges.md b/solutions/228. Summary Ranges.md
new file mode 100644
index 0000000..51eb514
--- /dev/null
+++ b/solutions/228. Summary Ranges.md	
@@ -0,0 +1,29 @@
+# [228. Summary Ranges](https://leetcode.com/problems/summary-ranges/)
+# 思路
+
+题意就是要求找出连续的区间。我们可以用start_i代表每个连续区间的开始下标，
+然后不断检查下一个数是不是连续的直到不连续为止，然后就将这个区间的结果push进结果数组，然后更新start_i处理下一个连续区间。
+
+# C++
+``` C++
+class Solution {
+public:
+    vector<string> summaryRanges(vector<int>& nums) {
+        if(nums.empty()) return vector<string>{};
+        int n = nums.size();
+        vector<string>res;
+        int start_i = 0, i = 0;
+        while(i < n){
+            while(i + 1 < n && nums[i] + 1 == nums[i + 1]) i++;
+            
+            string out = to_string(nums[start_i]);
+            if(i != start_i)
+                out += ("->" + to_string(nums[i]));
+            res.push_back(out);
+            
+            start_i = ++i;
+        }
+        return res;
+    }
+};
+```