引用实现字符串的交换

#include <iostream>
using namespace std;

void exchange(char* &r1, char* &r2){//r1,r2s指针的引用 也是指针
    char* temp;
    temp = r1;
    r1 = r2;
    r2 = temp;
}
int main(int argc, const char * argv[]) {
    char* str1 = "hello";
    char* str2 = "how are you";
    exchange(str1,str2);
    cout << str1 <<endl;
    cout << str2 <<endl;
    return 0;
}

报错：C++11不允许把字符串赋值给char *类型的变量

改为const之后，输出不正常了😓