简单的C ++代码将无法运行

Question

我的程序从字面上开始，提示输入1或2，然后输入，然后结束。 为什么这样做呢？ 我真的可以使用一些想法。 如果有人对如何更好地进行设置提出建议，我完全开放，我还没有很多经验。

#include <iostream>
#include <iomanip>
using namespace std;


void Weather(int weather)
{
    cout << "What clarity is the weather today in: " << endl;
    cout << "Clear" << endl << "Cloudy" << endl << "Dark";
    cin >> weather;
    cout << "Today's weather is " << weather;
    system("pause");

}

void WaterClarity(int waterclarity)
{
    cout << "What condition is the water in: " << endl;
    cout << "Clear" << endl << "Cloudy" << endl << "Murky";
    cin >> waterclarity;
}

void Season(int season)
{
    int month = 0;
    cout << "Using numbers 1-12 what month is it?";
    cin >> month;
    if (month == 1){
                cout << "The fish in season are: " << endl;
        cout << "Mahi Mahi" << endl << "Jack Crevalle" << endl << "Pompano";
        cout << "Redfish" << endl << "Spanish Mackrel";
    }
    else if (month == 2){
        cout << "The fish in season are: " << endl;
        cout << "Cobia" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl << "Pompano";
        cout << "Redfish" << endl << "Spanish Mackrel";
    }
    else if (month == 3){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Cobia" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl << "Pompano";
        cout << "Redfish" << endl << "Spanish Mackrel";
    }
    else if (month == 4){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Kingfish" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl << "Pompano";
        cout << "Redfish" << endl << "Spanish Mackrel" << endl << "Tarpon";
        }
    else if (month == 5){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Kingfish" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl;
        cout << "Tarpon";
    }
    else if (month == 6){
        cout << "The fish in season are: " << endl;
        cout << "Cobia" << endl << "Snapper" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl;
        cout << "Tarpon";
    }
    else if (month == 7){
        cout << "The fish in season are: " << endl;
        cout << "Cobia" << endl << "Snapper" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl;
        cout << "Tarpon";
    }
    else if (month == 8){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Redfish" << endl << "Mahi Mahi" << endl << "Jack Crevalle" << endl;
        cout << "Tarpon";
    }
    else if (month == 9){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Snapper" << endl << "Mahi Mahi" << endl << "Flounder" << endl;
        cout << "Tarpon" << endl << "Kingfish";
    }
    else if (month == 10){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Snapper" << endl << "Mahi Mahi" << endl << "Flounder" << endl;
        cout << "Tarpon" << endl << "Kingfish" << endl << "Redfish";
    }
    else if (month == 11){
        cout << "The fish in season are: " << endl;
        cout << "Blackfin Tuna" << endl << "Spanish Mackrel" << endl << "Mahi Mahi" << endl << "Flounder" << endl;
        cout << "Tarpon" << endl << "Kingfish" << endl << "Pompano";
    }
    else if (month == 12){
        cout << "The fish in season are: " << endl;
        cout << "Jack Crevalle" << endl << "Mahi Mahi" << endl << "Spanish Mackrel" << endl;
        cout << "Tarpon" << endl << "Kingfish" << "Pompano";
    }
}

int main()
{
    int selection = 0;
    cout << "Would you like to fish by lure or by season?"<<endl;
    cout << "Enter 1 for Lure, and 2 for Season.";
    cin >> selection;
        if (selection==1){
            void Weather(int weather);
            void WaterClarity(int waterclarity);


        }
        else if (selection == 2){
                void Season(int season);
        }
    system("pause");
    return 0;
}

Answer 1

实际上，有很多事情需要更改。

Ankit B所说的是真的，但仍然行不通。 为了调用他的陈述方式，您需要在主例程中声明weather ， waterclarity和season变量。 它看起来如下：

int main()
{
    int selection = 0;
    int weather = 0;
    int waterclarity = 0;
    int season = 0;

    cout << "Would you like to fish by lure or by season?"<<endl;
    cout << "Enter 1 for Lure, and 2 for Season.";
    cin >> selection;
        if (selection==1){
            Weather(weather);
            WaterClarity(waterclarity);


        }
        else if (selection == 2){
                Season(season);
        }
    system("pause");
    return 0;
}

添加关键字void在你的程序面前Weather ， WaterClarity和Season的内main例程由编译器看着是试图“重新定义”并已定义程序。

另外，事实是，在Weather例程中，您正在按值传递变量，但是在例程中，试图读取并设置weather变量的值。 如果希望能够在例程中设置变量值，则需要通过引用传递。

Answer 2

您以错误的方式调用函数。

您尚未在main function声明或初始化变量。

并且不接受用户的任何输入来初始化变量。

调用函数的正确方法是

试试这个代码

if (selection==1){
 Weather(weather);
 WaterClarity(waterclarity);  
 }
 else if (selection == 2){
    Season(season);
 }

但在此之前，您必须接受变量的输入。

int weather;
int waterclarity;
int season;