support bazel complie this project and format code.

practical_exercises/key_exercises/io_operator_overload.cpp

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+/* 输入输出运算符重载.cpp */
+/*
+   有一销售人员类Sales，其数据成员有姓名name，身份证号id，年龄age。
+   重载输入/输出运算符实现对Sales类数据成员的输入和输出。
+ */
+#include <cstring>
+#include <iostream>
+using namespace std;
+class Sales {
+private:
+  char name[10];
+  char id[18];
+  int age;
+
+public:
+  Sales(char *Name, char *ID, int Age);
+
+  friend Sales &operator<<(ostream &os, Sales &s); //重载输出运算符
+  friend Sales &operator>>(istream &is, Sales &s); //重载输入运算符
+};
+Sales::Sales(char *Name, char *ID, int Age) {
+  strcpy(name, Name);
+  strcpy(id, ID);
+  age = Age;
+}
+Sales &operator<<(ostream &os, Sales &s) {
+  os << s.name << "\t"; //输出姓名
+  os << s.id << "\t";   //输出身份证号
+  os << s.age << endl;  //输出年龄
+  return s;
+}
+Sales &operator>>(istream &is, Sales &s) {
+  cout << "输入雇员的姓名，身份证号，年龄" << endl;
+  is >> s.name >> s.id >> s.age;
+  return s;
+}
+int main() {
+  Sales s1("杜康", "214198012111711", 40); // L1
+  cout << s1;                              // L2
+  cout << endl;                            // L3
+  cin >> s1;                               // L4
+  cout << s1;                              // L5
+}