diff --git a/LeetCode-CN/665.cpp b/LeetCode-CN/665.cpp
new file mode 100644
index 0000000..b6beccf
--- /dev/null
+++ b/LeetCode-CN/665.cpp
@@ -0,0 +1,22 @@
+class Solution {
+public:
+    bool checkPossibility(vector<int>& nums) {
+        int nrev = 0;
+
+        for(int i=1; i<nums.size(); i++) {
+            if (nums[i-1] > nums[i]) {
+                if (nrev) return false;
+                nrev++;
+
+                if (i < 2) nums[i-1] = nums[i];
+                else if (nums[i-2] <= nums[i]) {
+                    nums[i-1] = nums[i-2];
+                } else {
+                    nums[i] = nums[i-1];
+                }
+            }
+        }
+
+        return nrev < 2;
+    }
+};