fix some error bugs and format the document.

practical_exercises/key_exercises/输入输出运算符重载.cpp

@@ -2,38 +2,48 @@
  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<iostream.h>
+#include <iostream>
-#include<string.h>
+#include <cstring>
-class Sales{
+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) {
+Sales::Sales(char *Name, char *ID, int Age)
+{
     strcpy(name, Name);
     strcpy(id, ID);
     age = Age;
 }
-Sales& operator<<(ostream &os,Sales &s) {
+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) {
+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;                       	
+{
+    cout << "输入雇员的姓名，身份证号，年龄" << endl;
+    is >> s.name >> s.id >> s.age;
     return s;
 }
-void main(){
+int main()
+{
     Sales s1("杜康", "214198012111711", 40); //L1
     cout << s1;								 //L2
     cout << endl;							 //L3
     cin >> s1;								 //L4
     cout << s1;								 //L5
+    return 0;
 }