C++ help - getline

Question

我已經做了兩個星期的C++了，我創建了一個非常簡單的程序，它允許用戶輸入他們的名字，然後輸出那裏的全名，這裏是代碼;

#include <iostream> 
#include <string> 

using namespace std; 

int main() 
{ 
    string first ; 
    string middle ; 
    string last; 

    cout << "What is your firstname?" << endl; 
    getline(cin, first); 
    cout << "Your firstname is "; 
    first = first; 
    cout << first << endl; 
    cout << endl; 

    cout << "What is your middle name?" << endl; 
    getline(cin, middle); 
    cout << "Your middle name is "; 
    middle = middle; 
    cout << middle << endl; 
    cout << endl; 

    cout << "What is your lastname?" << endl; 
    getline(cin, last); 
    cout << "Your lastname is "; 
    last = last; 
    cout << last << endl; 
    cout << endl; 

    cout << "Your full name is " << first + middle + last << endl; 

    system ("pause"); 
    return 0; 
} 

我遇到的問題是，它會在最後COUT

cout << "Your full name is " << first + middle + last << endl; 

不輸出空格任何幫助，將不勝感激！ 謝謝。

Answer 1

你的輸出線改爲

cout << "Your full name is " << first << " " << middle << " " << last << endl; 

Answer 2

那是因爲你沒有告訴它來寫，我想你想他們的空間。

我的猜測是，你的空間就在

"Your full name is " 

然後你想你first，middle和last字符串之間無空格罰款？ 但是你永遠不會在那裏添加任何空格。

，看起來像

<< first + middle + last << 

必須改變，以包含空格的部分

<< first + " " + middle + " " + last << 

所以，你在最後整個COUT應該

cout << "Your full name is " << first + " " + middle + " " + last << endl; 

Answer 3

#include <iostream> 
#include <string> 

using namespace std; 

int main() 
{ 
    string first ; 
    string middle ; 
    string last; 

    cout << "What is your firstname?\n"; 
    getline(cin, first); 
    cout << "Your firstname is " << first << "\n\n"; 

    cout << "What is your middle name?\n"; 
    getline(cin, middle); 
    cout << "Your middle name is " << middle << "\n\n"; 

    cout << "What is your lastname?\n"; 
    getline(cin, last); 
    cout << "Your lastname is " << last << "\n\n"; 

    cout << "Your full name is " << first +" "+ middle +" "+ last << "\n\n"; 

    system ("pause"); 
    return 0; 
}