我是C++的初學者,所以我只是在閱讀文章和書籍時將一些東西搞亂了。但我花了20分鐘時間重複閱讀這些內容,我無法分辨出它有什麼問題。編譯器在減去std :: strings時出錯
#include <iostream>
#include <string>
using namespace std;
int main()
{
cout << "Hello there, this is your personal simple calculator.";
cin.get();
cout << "Type in what you want to do. (Addition, Subtraction, Multiplication, Division)"<< endl;
string c;
getline (cin, c);
if (c == "Addition")
{
string a_1;
string a_2;
cout << "You chose addition. Press enter" << endl ;
cin.get();
cout << "Type in the first value: ";
getline(cin, a_1);
cout << "Type in the second value: ";
getline (cin, a_2);
cout << a_1 << " + " << a_2 << " = " << a_1 + a_2 << endl;
}
else
{
cout << "You spelled it wrong.";
return 0;
}
if (c == "Subtraction")
{
string s_1;
string s_2;
cout << "You chose subtraction. Press enter" << endl ;
cin.get();
cout << "Type in the first value: ";
getline (cin, s_1);
cout << "Type in the second value: ";
getline (cin, s_2);
cout << s_1 << " - " << s_2 << " = " << s_1 - s_2 << endl;
}
}
我得到這個作爲唯一的錯誤
42 83 C:\ Users \用戶傑森\桌面\課 - 頭文件\ LH1.cpp [錯誤]敵不過在 '操作符 - ' 'first_argument - second_argument'
我不明白。加法符號起作用,除了減法運算以外的所有內容。 所以我用別的
cout << first_argument << " - " << second_argument << " = " << first_argument - second_argument << endl;
亂七八糟的東西,但周圍是減法部分工作正常。我不明白。請幫助
請考慮一個更具描述性的標題。這個頭銜可能適用於數千個問題。 – chris 2014-08-28 22:23:15
'std :: string'沒有'operator-'。 – juanchopanza 2014-08-28 22:27:02
'std :: string'的'+'運算符是串聯的。沒有'operator-',我不知道你應該怎麼做。 – Blastfurnace 2014-08-28 22:27:34