【发布时间】：2013-09-09 23:56:26
【问题描述】：
我真的很困惑。我必须为一堂课制作这个实验室，我似乎无法让搜索只显示一个结果，而是一年中的所有月份。当我在一年中的月份输入 0 时，我似乎也无法弄清楚为什么它不显示 TotalRainfall。 谢谢。
#include <iostream>
#include <fstream>
const int MaxSize = 12; //How many weather lines will be available.
using namespace std;
struct WeatherInformation
{
int Month; //Months of the year
float TotalMonthsRainfall; //Total amount of rainfall
float HighTemp; //The Highest temperature of the month.
float LowTemp; //The Lowest temperature of the month.
float AverageTemp; //The Average temperature of the month.
};
WeatherInformation WeatherArray[MaxSize]; //Declaring a month array of MaxSize
void ReadFile(ifstream& MyinFile, WeatherInformation WeatherArray[]);
void WeatherMonthSearch (WeatherInformation WeatherArray[]);
int main()
{
float TotalRainfall = 0;
int count = 1; //Counts how many times the for loop goes.
int MonthOfWeather; //User input of the month.
char ProgramRedo; //User input if they want to reuse the program.
char exit_char; //User input to exit the program.
ifstream MyinFile; //Variable that uses file.
ReadFile (MyinFile, WeatherArray); //Call ReadFile Function
WeatherMonthSearch (WeatherArray); //Call WeatherMonthSearch Function
MyinFile.close(); //Closes file.
}
//Brett Holmes
//4/30/2013
//PreCondition:You need a file labeled weather.dat
//PostCondition: It puts the file variables into an array.
void ReadFile(ifstream& MyinFile, WeatherInformation WeatherArray[])
{
float TotalRainfall = 0;
char exit_char;
int count = 0;
int Month = 0;
cout << "Your Weather Machine" << endl << endl;
MyinFile.open("weather.dat");
if (!MyinFile)
{ //no
cout << "Can't open input file." << endl; //Tests the right file.
char exit_char; //End Program
cout << "Press any key to exit" << endl;
cin >> exit_char;
}
for(count = 1; count < MaxSize; count++) //Puts the file variables in the array.
{
WeatherArray[count].Month = WeatherArray[count].Month + 1;
MyinFile >> WeatherArray[count].TotalMonthsRainfall;
MyinFile >> WeatherArray[count].HighTemp;
MyinFile >> WeatherArray[count].LowTemp;
(WeatherArray[count].AverageTemp = ((WeatherArray[count].HighTemp + WeatherArray[count].LowTemp)/2));
(TotalRainfall = TotalRainfall + WeatherArray[count].TotalMonthsRainfall);
}
}
//Brett Holmes
//4/30/13
//PreCondition:You need to have the months already put into an array in a struct.
//PostCondition:Outputs the rainfall stats the user puts in then asks to run again.
//Outputs a error message if they type in the month wrong.
void WeatherMonthSearch (WeatherInformation WeatherArray[])
{
float TotalRainfall;
int months;
int MonthOfWeather;
char ProgramRedo;
do
{
bool MonthFound = false;
cout << "Please input the number of the Month. Ex. 1=Jan. 2=Feb. etc \n\n";
cin >> MonthOfWeather;
for(int i = 1; i <= MaxSize; i++)
{
months = WeatherArray[i].Month;
if(months == MonthOfWeather ) //Finds the artist and outputs the results
{
cout << "\nTotal Months Rainfall: " << WeatherArray[i].TotalMonthsRainfall << " \n";
cout << "Highest Temperature: " << WeatherArray[i].HighTemp << " \n";
cout << "Lowest Temperature: " << WeatherArray[i].LowTemp << " \n";
cout << "Average Temperature: " << WeatherArray[i].AverageTemp << " \n";
MonthOfWeather = true;
}
}
if(MonthOfWeather == 0)
{
cout << "The total rainfall for the year is: " << TotalRainfall << ".";
}
if(MonthFound == false)
{
cout << "\nMonth Number error. Month not found. Try again.\n\n";
MonthOfWeather = false;
}
cout << "Would you like to look up another month of weather?\n";
cout << "Enter a 'Y' if yes and 'N' if no.\n";
cin >> ProgramRedo;
}while(ProgramRedo == 'Y');
}
【问题讨论】：
-
您知道您没有填充数组中的第一个条目，对吗？而
WeatherMonthSearch正在访问超出数组大小的一个元素，进入未定义行为的领域。 -
@WhozCraig：也没有使用数组的第一个元素...但是 MaxSize 需要为 13 才能覆盖使用 1..12 的数组。
-
...另外，
MonthOfWeather = true;没有意义... -
这看起来像一个非常可疑的逻辑
WeatherArray[count].Month = WeatherArray[count].Month + 1;，考虑到WeatherArray[...].Month之前没有初始化。你确定他们都需要等于1吗？不应该只是WeatherArray[count].Month = count;吗？ -
@us2012 我认为应该是
MonthFound，或者看起来是这样。