Question

所以我有班级IntArray。这就是它的名字所说的，带有边界检查的动态整数数组类和那种东西。这是该类的方法和变量。

public:
    IntArray();
    IntArray(unsigned int length);
    IntArray(const IntArray& ia);
    ~IntArray();
    int length() const { return size; }
    void resize(unsigned int length);
    void insertBefore(int value, int index);
    int& operator[] (int i);
    IntArray& operator=(const IntArray& ia);
    friend ostream& operator<< (ostream& out, const IntArray& array);
 private:
    unsigned int size;
    unsigned int actualSize;
    int * data;
    const static int DEFAULT = 0; // Default fill value
    const static int INCREMENT = 20; // Default value to increase size with
    void fillWithDefault(int end, int start = 0);
    void copyElements(int *toArray, int end, int start = 0, int offsetSize = 0, int offsetIndex = 0) const;
    void resize(unsigned int length, unsigned int offset);

以下是主要代码：

IntArray a (6);
for ( int i =0; i <6;++ i ){
    a [ i ]= i * i ;
}
cout << "BEFORE C" << endl;
IntArray c;
cout << "AFTER C" << endl;
c = a;

我已经测试过每一个函数并且它有效，除非我启动此代码时它永远不会到达IntArray c;行。

错误：此应用程序已请求Runtime以不寻常的方式终止它。

额外的怪癖：在调试中运行，一切都很好。

编辑：额外代码

IntArray::IntArray() {
    size = 0;
    actualSize = INCREMENT;
    data = new int[actualSize];
}

IntArray::IntArray(unsigned int length)
    : size(length), actualSize(length) {
    data = new int[length];
    fillWithDefault(length);
}

IntArray::IntArray(const IntArray& ia)
    : size(ia.size), actualSize(ia.actualSize) {
    data = new int[actualSize];
    ia.copyElements(data, size);
}

IntArray::~IntArray() {
    delete [] data;
}

void IntArray::resize(unsigned int length) {
    resize(length, length < size? length:size);
}

void IntArray::insertBefore(int value, int index) {
    resize(size+1, index);
    data[index] = value;
}

void IntArray::resize(unsigned int length, unsigned int offset) {
    unsigned int tempSize = size;
    unsigned int startIndex = offset; // Where to increase the array?
    int * theData = data;
    size = length;

    if(length > actualSize) { // Entire array needs to be copied (new data!)
        actualSize = length + INCREMENT;
        theData = new int[actualSize];
        startIndex = 0;
    }

    if(length > tempSize)
        copyElements(theData, tempSize, startIndex, (length-tempSize), offset);

    if(length > actualSize) {
        delete [] data; // Delete former data and assign new
        data = theData;
    }

    if(length > tempSize) // Fill remainder with DEFAULT
        fillWithDefault(length, offset);
}

int& IntArray::operator[] (int i) {
    if(i < 0 || (unsigned int)i >= size)
        throw "\nIndex out of bounds\n";
    return data[i];
}

IntArray& IntArray::operator=(const IntArray& ia) {
    if(this != &ia) {
        size = ia.size; // Copy variables
        actualSize = ia.actualSize;
        delete [] data; // Get rid of old data
        data = new int[actualSize]; // Create new data and copy elements
        ia.copyElements(data, size);
    }
    return *this;
}

ostream& operator<< (ostream& out, const IntArray& array) {
    int size = array.size;
    for(int i = 0; i < size; ++i) {
        out << array.data[i];
        if(i < size-1)
            out << ' ';
    }
    return out;
}

void IntArray::fillWithDefault(int end, int start) {
    if(start < 0 || start > end || (unsigned int)end > size)
        throw "\nArray can't be filled with invalid indexes\n";

    for(int i = start; i < end; i++)
            data[i] = DEFAULT;
}

void IntArray::copyElements(int *toArray, int end, int start, int offsetSize, int offsetIndex) const {
    if(start < 0 || start > end || (unsigned int)end > size)
        throw "\nArray can't be filled with invalid indexes\n";

    int offset = 0;
    for(int i = start; i < end; ++i) {
        if(i == offsetIndex)
            offset = offsetSize;
        toArray[i+offset] = data[i];
    }
}

未初始化的变量崩溃程序

0 个答案: