Question

#include <iostream>
#include <math.h>
#include <string.h>

using namespace std;

int main ()
{
    cout << "My Funny Program";

    do {
        string Answer;
        cout << "Are you stupid? (Yes/No)";
        cin >> Answer;
        cout << endl;
        cout << "Perhaps you are lying?";
    }
    while (Answer == "No");

    cout << "Thank you for your honesty." << endl;

    return 0;
}

我一直在尝试让这段代码正常工作;但是，每次出现“在此范围内未声明答案”错误时，都会弹出。

Answer 1

我认为如果块本身，while条件超出了范围。所以string Answer必须在循环之外定义。

样式建议：Caps用于类或常量或宏。避免将它们用于变量。

Answer 2

 do{

        string Answer;
        cout<< "Are you stupid? (Yes/No)";
        cin>>Answer;
        cout<< endl;
        cout<< "Perhaps you are lying?";

    }

    while (Answer == "No");

由于在do-while内部声明了答案，while部分不知道答案是否存在。

您必须在do-while

之前声明答案

Answer 3

您的Answer变量目前仅在声明它的{}之间（在循环体内）。您需要在循环之前声明Answer。

string Answer;
do {
    cout << "Are you stupid? (Yes/No)";
    cin >> Answer;
    cout << endl;
    cout << "Perhaps you are lying?";
}
while (Answer == "No");

Answer 4

有趣的节目......

在do-while循环之外声明答案将解决您的问题。

string Answer;
do {

        cout << "Are you stupid? (Yes/No)";
        cin >> Answer;
        cout << endl;
        cout << "Perhaps you are lying?";
    }
    while (Answer == "No");

此外，您应该使用<string>代替<string.h>

Answer 5

do {
        string Answer;
        cout << "Are you stupid? (Yes/No)";
        cin >> Answer;
        cout << endl;
        cout << "Perhaps you are lying?";
    }
    while (Answer == "No");

在do中，您声明了一个字符串变量Answer。然后Answer被推入堆栈，但是，当程序强制}时，变量将被加载，这意味着，在while语句中，Answer已经释放，编译器将Answer视为未定义的变量。

错误：＆＃39;回答＆＃39;在这方面没有申明

5 个答案: