进程 中的 string& operator=()函数

str1.operator=(str2);
str1.operator=(ch);
str1.operator=(const char* s);

#include<iostream>
using namespace std;
int main()
{
string str ="C Programs";
string str1="Java Programs";
str.operator=(str1);
cout<<str;
return 0; 
}

#include<iostream>
using namespace std;
int main()
{
string str ="Maths is my favorite subject";
char* s ="Science is my favorite subject";
str.operator=(s);
cout<<str;
return 0; 
}

#include<iostream>
using namespace std;
int main()
{
string str ="java";
char ch='C';
str.operator=(ch);
cout<<str;
return 0; 
}