Question

我写了两个类Vector和Matrix，其中我使用copy将动态数组从一个对象复制到另一个对象，用于复制构造函数和运算符=。如果我将这些类的每个代码分别放到main，它可以正常工作，但如果我同时放入它们，则会发生错误。这是我的代码：

matrix.h

#include <iostream>
#include <iomanip>
#include <stdexcept>

using namespace std;

template <class U>
class Matrix {
    int row, col;
    U **data;

    public:
        Matrix(int, int);
        Matrix(const Matrix&);
        Matrix operator = (const Matrix&);
        ~Matrix();
};

template <class U>
Matrix<U>::Matrix(int row, int col) {
    this->row = row;
    this->col = col;
    data = new U *[row];
    for (int i = 0; i < col; ++i)
        data[i] = new U[col];
}

template <class U>
Matrix<U>::Matrix(const Matrix& mt) {
    if (this != &mt) {
        row = mt.row;
        col = mt.col;
        data = new U *[row];
        for (int i = 0; i < col; ++i)
            data[i] = new U[col];
        for (int i = 0; i < row; i++)
            copy(&mt.data[i][0], &mt.data[i][col+1], data[i]);
            //memcpy(data[i], mt.data[i], col*sizeof(data[i]));
    }
}

template <class U>
Matrix<U>::~Matrix() {
    for (int i = 0; i < row; i++) {
        delete [] data[i];
    }
    delete [] data;
}

template <class U>
Matrix<U> Matrix<U>::operator = (const Matrix& mt) {
    if (row == mt.row and col == mt.col) {
        for (int i = 0; i < row; i++)
            copy(&mt.data[i][0], &mt.data[i][col], data[i]);
            //memcpy(data[i], mt.data[i], col*sizeof(data[i]));
        return *this;
    }
    else throw runtime_error("Matrices must have same size.");

    return *this;
}

vector.h

#include <iostream>
#include <stdlib.h>
#include <stdexcept>

using namespace std;

template <class type>
class Vector {
    int size;
    type *data;

    public:
        Vector(int);
        Vector(const Vector&);
        ~Vector();
        Vector operator = (const Vector&);
};

template <class type>
int Vector<type>::get_size() {
    return size;
}

template <class type>
Vector<type>::Vector(int size) {
    if (size < 2) throw runtime_error("Size must be greater than 1.");
    else {
        this->size = size;
        data = new type[size];
    }
}

template <class type>
Vector<type>::Vector(const Vector& that) {
    size = that.size;
    data = new type[size];
    copy(&that.data[0], &that.data[size+1], data);
    //memcpy(data, that.data, size*sizeof(data));
}

template <class type>
Vector<type> Vector<type>::operator = (const Vector& that) {
    cout<<"Assigning..."<<endl;
    if (size == that.size) {
        copy(&that.data[0], &that.data[size], data);
        //memcpy(data, that.data, size*sizeof(data));
        return *this;
    }
    else throw runtime_error("Vectors must have same size.");
    return *this;    
}

的main.cpp

#include <iostream>
#include "vector.h"
#include "matrix.h"
#include <stdexcept>

using namespace std;

int main() {
    try {
        Vector<int> a(3), c(3);
        Matrix<int> b(2,2), d(2,2);
        // Vector
        cin>>a;
        cout<<a;
        c=a;
        cout<<c;

        //Matrix
        cin>>b;
        d = b;
        cout<<d;
    }
    catch (exception &e) {
        cout<<e.what()<<endl;
    }
}

和错误：

vector_matrix_poly_demo: malloc.c:2372: sysmalloc: Assertion `(old_top == (((mbinptr) (((char *) &((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct malloc_chunk, fd)))) && old_size == 0) || ((unsigned long) (old_size) >= (unsigned long)((((__builtin_offsetof (struct malloc_chunk, fd_nextsize))+((2 *(sizeof(size_t))) - 1)) & ~((2 *(sizeof(size_t))) - 1))) && ((old_top)->size & 0x1) && ((unsigned long) old_end & pagemask) == 0)' failed.
Aborted (core dumped)

其余的代码（重载运算符>>和<<）我没有放在这里因为它工作正常。这个错误只是在linux中，我使用的是Ubuntu 14.04，如果我先将copy替换为memcpy或Matrix代码块，则不会发生错误。

最好的问候，抱歉我的英语不好。

C ++：复制动态数组导致Linux

0 个答案: