实验C++ string库的常用函数
#include <bits/stdc++.h>
using namespace std;
int main() {
string str="abc";
cout << str.back()<<endl;//读取末位字符串
cout << str.front()<<endl;//读取首位字符串
str.push_back('s');
cout << str<<endl;//末位添加字符
str.pop_back();
cout << str<<endl;//删除末位字符
cout << str.size()<<endl;//字符串大小
cout << str.at(1)<<endl;//查找指定位置字符
cout << str.find('b')<<endl;//查找指定字符位置
str += string(2, str.back()); //字符串末尾添加2个末尾字符
cout << str<<endl;
str = "#" + string(2, str[0]) + string(2, str[1]) + string(2, str[2]); //拼接字符串
cout << str<<endl;
cout << str.substr(1,2)<<endl;//截取字符串
cout << str.replace(1,1,3,'x')<<endl;//1到1的位置换成3个x
return 0;
}