Question

初学者程序员在这里。下面的代码能够在不输出任何错误的情况下运行;但是，它不输出任何东西，它永远不会停止运行。并且，我无法弄清楚为什么在花费无数个小时之后就是这种情况。

struct包含动态数组，用于在读入文件后存储整数和字符串。此文件（weatherdata.txt）包含城市名称，高温和低温列表。然后，在读取这些行之后将它们存储到动态数组中，并在必要时将动态数组的大小加倍（大小加倍）。

要查看这是否有效，我想输出城市列表，但这不起作用。我在某处错误地编写了代码吗？

#include <iostream> 
#include <fstream>    

using namespace std;

//Declaring struct
struct dynArr{
    string *cityName;
    int *hiTemp;
    int *loTemp;    
    int size;
};

//Function read in the desired file
void openFile ( dynArr & arr1 ){
    arr1.size = 10;
    arr1.cityName = new string[arr1.size];
    arr1.hiTemp = new int[arr1.size];
    arr1.loTemp = new int[arr1.size];

    string city;
    int hi, lo;

    ifstream is; 
    is.open ("weatherdata.txt ", ios::in);

    int i = 0;
    is >> city;
    while ( ! is.eof() ){
        is  >>  hi >> lo;

        //Double the size of dynamic arrays 
        if ( i >= arr1.size){

            string *tempStr1;
            tempStr1 = new string[arr1.size*2];

            int *tempInt1;
            tempInt1 = new int[arr1.size*2];
            int *tempInt2;
            tempInt2 = new int[arr1.size*2];

            for (int a = 0; a < arr1.size; a++){
                tempStr1[a] = arr1.cityName[a];
                tempInt1[a] = arr1.hiTemp[a];
                tempInt2[a] = arr1.loTemp[a];
            }

            delete[] arr1.cityName;
            delete[] arr1.hiTemp;
            delete[] arr1.loTemp;

            arr1.cityName = tempStr1;
            arr1.hiTemp = tempInt1;
            arr1.loTemp = tempInt2;

            arr1.size = arr1.size*2;
        }

        //Store the read lines from file into the dynamic arrays
        arr1.cityName[i] = city;
        arr1.hiTemp[i] = hi;
        arr1.loTemp[i] = lo;

        i++;
        is >> city; 
    }

    for (int a = 0 ; a < i ; a++)
        cout << a << ". " << arr1.cityName[a] << endl;
}

int main(int argc, char *argv[]) {

    dynArr arr1;
    openFile(arr1);
}

Answer 1

中的文件名和结束引号之间有空格

is.open ("weatherdata.txt ", ios::in);

程序继续运行，没有任何输出

1 个答案: