c++ - 数组，removeFirst() 不工作？

Question

我创建了一个应该删除数组的第一个元素的方法，但是当我运行我的代码时，调试器出现故障，我不确定为什么。

这是我的 removeFirst() 方法:

Loan & ListOfLoans ::  removeFirst(){
    index = 0;
    //determine if the container needs to be shrunk
    if((numberOfElements < capacity/4) && (capacity >= 4)){ // shrink container when     array is 1/4 full
        cout<<"shrinking array! \n";
        Loan ** temp = elements;
        elements = new Loan * [numberOfElements/2];
        //copy temp array to elements
        for(int i = 0; i<numberOfElements; i++){
            temp[i] = elements[i];
            numberOfElements = numberOfElements/2;
            delete [] temp;
        }
    }
    numberOfElements--;
    return **elements;
} 

还有我的头文件:

#include <iostream>
#include "loan.h"

using namespace std;

class ListOfLoans {

public:
ListOfLoans(int initial_size=4);

~ListOfLoans(void);


 void add(Loan & aLoan);
 Loan & first() ;
 Loan & removeFirst();
   // answer the first element from the list and remove it from the list
    // if the resulting list is more than three quarters empty release some memory
 Loan & removeLast(); 
   // answer the last element from the list and remove it from the list
    // if the resulting list is more than three quarters empty release some memory
 Loan & next();
 int size(); 

private: 
Loan ** elements; //actuall stuff in the array m_pnData;
int numberOfElements; //number of elements in the list  stize of the array? m_nLength
int capacity; //size of the available array memory 
int index; //used to help with the iteration
};

Answer 1

尝试将 delete [] temp; 移到 for 循环下。

看起来一个问题可能是 delete [] temp; 在 for 循环中被重复调用。通过循环的第一次迭代，与 temp 关联的内存将被释放。循环中的后续迭代将访问释放的内存。

可能还有其他问题。查看调试器的输出会很有帮助。