Question

我正在尝试做一些C ++练习，但是我在构建时遇到了错误，这不仅仅是跳出来。我错过了什么？在几年前完成它之后，我只是从C＃等回到C ++。

[ERROR] 语法错误：'return' [/ ERROR]

#include <iostream>
using namespace std;

/* Pre-compiler directives / macros */
#define isValidDrinkChoice(Choice,MaxNumDrinks) ((Choice < MaxNumDrinks) && (Choice > 0))

/* Primary Entry Point for Executable */
int main(const int & argc, char * argv[]){

    const int MaxNumDrinks = 4;
    char ** Drinks;
    Drinks = new char* [MaxNumDrinks];
    Drinks[0] = "Soda";
    Drinks[1] = "Water";
    Drinks[2] = "Coffee";
    Drinks[3] = "Tea";
    Drinks[4] = "Perrier Sparkling Water";

    int Choice = -1;
    do while(!isValidDrinkChoice(Choice, MaxNumDrinks)) {
        cout << "Please select your favorite drink\r\n\r\n" << endl;
        for (int x = 0; x < MaxNumDrinks; x++) cout << "\t" << Drinks[x] << endl;
        cin >> Choice;
        if (isValidDrinkChoice(Choice, MaxNumDrinks)) cout << "\r\n\r\n" << "You chose " << *Drinks[Choice] << endl;
    }
    return 0;
}

Answer 1

我不认为C ++中有do while这样的东西。它是do { ... } while (expression);。或while (expression) { ... }。

Answer 2

更正后的代码采样需要替换的while循环

#include <iostream>

namespace {
  bool isValidDrinkChoice(int Choice, int MaxNumDrinks) {
    return ((Choice < MaxNumDrinks) && (Choice >= 0));
  }
}

/* Primary Entry Point for Executable */
int main() {
    using namespace std;   

    const char *Drinks[] = {
      "Soda", "Water", "Coffee", "Tea", "Perrier Sparkling Water" };
    const int MaxNumDrinks = sizeof(Drinks) / sizeof(*Drinks);

    int Choice = -1;
    do  {
        cout << "Please select your favorite drink\r\n\r\n" << endl;
        for (int i = 0; i < MaxNumDrinks; i++) 
          cout << Drinks[i] << endl;

        cin >> Choice;

        if (isValidDrinkChoice(Choice, MaxNumDrinks)) 
          cout << "\r\n\r\n" << "You chose " << Drinks[Choice] << endl;
    } while(!isValidDrinkChoice(Choice, MaxNumDrinks) && cin) ;

    return cin.good() ? 0 : 1;
}

追踪奇怪的错误

2 个答案: