使用指针的问题与动态数组 [英] Problems using pointers with an dynamic array

问题描述

我从读infile中整数和使用指针将它们添加到一个int数组。

I am reading integers from an infile and adding them to an int array using pointers.

我已经通过code多次，一切似乎符合逻辑跟踪，我没有得到任何语法错误或警告的编译器，我不知道什么是错的。

I have traced through the code multiple times and everything seems to flow logically and I am not getting any syntax errors or warnings in the compiler so I'm not sure what's wrong.

该计划要求我们使用数组而不是载体，否则我不认为我会被有这些问题。

This program requires us to use arrays and not a vector or else I don't think I would be having these problems.

现在我的输出是阅读各种扭曲。我知道它与指针做，但我在此刻损失。

Now my output is reading all kinds of screwy. I know it has to do with the pointers but I am at a loss at the moment.

INFILE：

3
456
593
94
58
8
5693
211

输出：

The items in the array are as follows.
7476376, 7475472, -17891602, 17891602, -17891602, -17891602, -17891602, -178916

collections.h

collections.h

class collections
{
    public:
        collections();
        void add(int);  //adds the value to the array.
        void print();  //prints item of the array comma separated.
        ~collections();
    protected:
        int arraySize;
        int *array;
};

构造器：

collections::collections()
{
    arraySize = 1;
    array = new int[arraySize];
}//done

无效地址：

void collections::add(int value) //adds the value to the array.
{
    //initial add to master array.
    if (arraySize == 1)
    {
        array[0] = value;
        arraySize++;
    }

    //every other add to master array.
    else
    {
        //temp array.
        int *tempArray = new int[(arraySize)];

        //copies old array into temp array.
        for (int i = 0; i < arraySize-1; i++)
        {
            tempArray[i] = array[i];
        }

        //adds new incoming value to temp array.
        tempArray[(arraySize-1)] = value;

        //new master array
        delete [] array;
        int *array = new int[arraySize];

        //copies temp to master array.
        for (int j =0; j < arraySize; j++)
        {
            array[j] = tempArray[j];
        }

        //cleanup
        delete [] tempArray;
        arraySize ++;
    }
} //done

无效打印：

void collections::print() //prints item of the array comma separated.
{
   cout << "The items in the array are as follows.\n";
    for (int i = 0; i < arraySize; i++)
    {
        cout << array[i] << ", ";
    }
}//done

对不起，我知道这可能很简单，但对我的生活我看不到的问题。

Sorry, I know this might be simple but for the life of me I can't see the problem.

推荐答案

您意外宣布的本地副本阵列将覆盖类的成员：

You accidentally declared a local copy of array which overrides the class member:

//new master array
delete [] array;
int *array = new int[arraySize];
^^^^^

删除为int * 从最后一行，其余的看起来不错。

Remove the int * from that last line and the rest looks okay.

PS：你有没有使用的std ::矢量＆lt考虑; INT＆GT;

PS: Have you considered using std::vector<int>?

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