diff --git a/STL/STL-unordered_map/unordered_map.cpp b/STL/STL-unordered_map/unordered_map.cpp
new file mode 100644
index 0000000..a056fce
--- /dev/null
+++ b/STL/STL-unordered_map/unordered_map.cpp
@@ -0,0 +1,40 @@
+#include <unordered_map>
+#include <iostream>
+#include <string>
+using namespace std;
+
+class hashdef{
+public:
+	//template<class T>，不太好分类型，就直接用string了 
+	size_t operator()(const string& a) const{//这里必须有const，在hash内部会把其当const调用 
+	//同样不能有static，调用需要用到this 
+		int hash;
+		int seed = 114514;
+		for(char x : a){	
+			hash += static_cast<int>(x)*31 + seed;
+			hash %= 1009;
+		}
+		return hash;
+	}
+};
+int main(){
+	hashdef a;
+	unordered_map<string, string, hashdef> m1{make_pair("1","111")};
+	unordered_map<string, string> m2;
+	m1.insert({make_pair("2","222"),make_pair("3","333"),make_pair("6","666"),make_pair("5","555")});
+	//下面首先查看哈希值
+	cout << a("1") << " " << a("2") << " " << a("3") << " " << a("5") << " " << a("6") << endl;
+	m1.rehash(1000);//重新设置桶的个数为1009，配合hash(此时会重新计算所有hash)
+	m2.max_load_factor(0.7f);//重新设置-控制扩容-负载因子=元素个数/桶个数，这里是平均每个桶最多0.7个元素
+	cout << "bucket_count: " << m1.bucket_count() << endl;//hashtable_policy.h中的质数表跳转到最近的大于n的数 
+	cout << m1.max_load_factor() << " " << m1.load_factor() << endl;
+	m1["7"] = "777";
+	cout << m1.at("6") << " " << m1["5"] << " " << m1.find("6")->second << endl;
+	return 0;
+}
+/*
+1007 29 60 122 153
+bucket_count: 1031
+1 0.00484966
+666 555 666
+*/
diff --git a/STL/STL-unordered_map/unordered_multimap.cpp b/STL/STL-unordered_map/unordered_multimap.cpp
new file mode 100644
index 0000000..a390606
--- /dev/null
+++ b/STL/STL-unordered_map/unordered_multimap.cpp
@@ -0,0 +1,20 @@
+//用法和unordered_map - multimap一致 
+#include <unordered_map>
+#include <iostream>
+using namespace std;
+int main(){
+	unordered_multimap<int, int> m;
+	m.insert({make_pair(1,111), make_pair(2,222), make_pair(3,333), make_pair(8,888), make_pair(6,666), make_pair(5,555)});
+	m.insert({make_pair(1,11), make_pair(2,22), make_pair(1,1)});
+	cout << m.count(1) << " " << m.find(1)->first << "," << m.find(1)->second << endl;
+	m.erase(m.find(1));
+	cout << m.count(1) << " " << m.find(1)->first << "," << m.find(1)->second << endl;
+	m.erase(1);
+	cout << m.count(1) << endl;
+	return 0;
+}
+/*
+3 1,1
+2 1,11
+0
+*/