diff --git a/main.cpp b/main.cpp
index d76cce7..4003850 100644
--- a/main.cpp
+++ b/main.cpp
@@ -3,6 +3,7 @@
 #include <variant>
 
 // 请修复这个函数的定义：10 分
+template <class T>
 std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
     os << "{";
     for (size_t i = 0; i < a.size(); i++) {
@@ -15,20 +16,52 @@ std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
 }
 
 // 请修复这个函数的定义：10 分
-template <class T1, class T2>
+template <class T1, class T2, class T0 = decltype(T1{} + T2{})>
 std::vector<T0> operator+(std::vector<T1> const &a, std::vector<T2> const &b) {
     // 请实现列表的逐元素加法！10 分
     // 例如 {1, 2} + {3, 4} = {4, 6}
+    std::vector<T0> res;
+    
+    size_t len = a.size() < b.size() ? a.size() : b.size();
+    for(size_t i=0; i<len; ++i)
+        res.push_back(a[i] + b[i]);
+    
+    return res;
 }
 
 template <class T1, class T2>
 std::variant<T1, T2> operator+(std::variant<T1, T2> const &a, std::variant<T1, T2> const &b) {
     // 请实现自动匹配容器中具体类型的加法！10 分
+    return std::visit([&](auto const &x, auto const &y) -> std::variant<T1, T2>{
+        return x + y;
+    }, a, b);
+}
+
+template <class T1, class T2, class T3>
+auto operator+(std::variant<T1, T2> const &a, std::vector<T3> const &b){
+    return std::visit([&](auto const &vec){
+        return vec + b;
+    }, a);
+}
+
+template <class T1, class T2, class T3>
+auto operator+(std::vector<T3> const &a, std::variant<T1, T2> const &b){
+    return b + a;
 }
 
 template <class T1, class T2>
 std::ostream &operator<<(std::ostream &os, std::variant<T1, T2> const &a) {
     // 请实现自动匹配容器中具体类型的打印！10 分
+    os << "{";
+    std::visit([&](auto const &vec){
+        for (size_t i = 0; i < vec.size(); i++) {
+            os << vec[i];
+            if (i != vec.size() - 1)
+                os << ", ";
+        }        
+    }, a);
+    os << "}";
+    return os;
 }
 
 int main() {