diff --git a/solution/0000-0099/0001.Two Sum/README.md b/solution/0000-0099/0001.Two Sum/README.md
index 8cb31ebef6a58d45b60613bdfddbdb979577fdd9..ac2fdaf7488d45c87d149f08b6178fd45e2f5c57 100644
--- a/solution/0000-0099/0001.Two Sum/README.md	
+++ b/solution/0000-0099/0001.Two Sum/README.md	
@@ -107,10 +107,10 @@ class Solution {
 public:
     vector<int> twoSum(vector<int>& nums, int target) {
         unordered_map<int, int> m;
-        for (int i = 0;; ++i) {
+        for (int i = 0; i < nums.size(); ++i) {
             int x = nums[i];
             int y = target - x;
-            if (m.count(y)) {
+            if (m.find(y) != m.end()) {
                 return {m[y], i};
             }
             m[x] = i;