C++ <getline及atoi>

#include <iostream>
#include <string>  // 用于C++ string类的操作
#include <cctype> // 用于C字符串的拷贝、比较、追加 等，strcpy(), strcmp(), strcat()
#include <cstdlib> // 用于exit(EXIT_FAILURE)及atoi即：alpha to interge 的缩写

int main() {
    using std::cout;
    using std::cin;
    using std::string;

    /* 7890 + 943210 = 951100
     * atoi 函数只能用C类型字符串转数字，不能对string类操作
     * 因为字符串类型最后一位要存放结束符'\0'所以定义数组大小时应考虑为存放'\0'预留空间
     */
    char str1[5] = "7890";
    char str2[7] = "943210";
    int n1 = atoi(str1);
    int n2 = atoi(str2);
    int sum = n1+ n2;
    cout << n1 << " + " << n2 << " = " << sum << '\n';

    /* Enter your name: may be you are right
     * But i can't belive it.
     * may be you are right
     * But
     */
    string a, b;
    cout << "Enter your name: ";
    getline(cin, a) >> b;
    cout << a << '\n' << b << '\n';

    /* Are you ok?
     * I am not sure, maybe i need rest a monments.
     * I am not s    
     */
    string c;
    cout << "Are you ok?\n";
    getline(cin, c, 'u');
    cout << c << '\n';
}