感谢您的帮助。
我必须调整一个能够从数组中删除重复项的函数。目前，我得到了我甚至不理解的奇怪输出，每当我尝试清理重复的功能时，我都没有达到预期的效果。这是代码。
的main.cpp
#include <iostream> // For cout and cin
#include <string> // For string objects
#include "Set.h" // For ADT Set
using namespace std;
int main()
{
//Creating a set to hold our numbers
Set<int> a_set;
//Checking if a_set is empty
cout << "This is the empty set, and IsEmpty() returns "
<< a_set.IsEmpty() << endl;
//creating an empty array
int Array[] = {1};
//Checking if the set now has a single items
cout << "This set should have a single item, and a_set.Contains "
<< a_set.Contains(Array[1]) << endl;
//Removing the item placed in a_set.
a_set.Remove(Array[1]);
//Verifying that the set is empty again.
cout << "This is the empty set, and IsEmpty() returns "
<< a_set.IsEmpty() << " The set is now empty and ready for values." << endl;
//Adding items in order given
a_set.Add(Array[1]);
a_set.Add(Array[10]);
a_set.Add(Array[3]);
a_set.Add(Array[10]);
a_set.Add(Array[5]);
a_set.Add(Array[10]);
//Getting current size of a_set
int size = a_set.GetCurrentSize();
cout << "The Array should be size=4. Size = " << size << endl;
//Checking that the items that we placed in the set are correct
cout << "Number 1 should be pressent in a_set. Return: "
<< a_set.Contains(Array[1]) << endl;
cout << "Number 3 should be pressent in a_set. Return: "
<< a_set.Contains(Array[3]) << endl;
cout << "Number 5 should be pressent in a_set. Return: "
<< a_set.Contains(Array[5]) << endl;
cout << "Number 10 should be pressent in a_set. Return: "
<< a_set.Contains(Array[10]) << endl;
int v = 0;
do
{
cout << Array[v] << endl;
v++;
}while (v < 7);
return 0;
}; // end main
现在这是我的功能。这是我之前甚至试图删除重复....
function.cpp
#include "Set.h"
#include <cstddef>
template<class ItemType>
Set<ItemType>::Set() : item_count_(0), max_items_(kDefaultSetSize_)
{
} // end default constructor
template<class ItemType>
int Set<ItemType>::GetCurrentSize() const
{
return item_count_;
} // end getCurrentSize
template<class ItemType>
bool Set<ItemType>::IsEmpty() const
{
return item_count_ == 0;
} // end isEmpty
// Made changes to deny duplicate items in an array.
template<class ItemType>
bool Set<ItemType>::Add(const ItemType& new_entry)
{
bool has_room_to_add = item_count_ < max_items_;
if (has_room_to_add)
{
items_[item_count_] = new_entry;
item_count_++;
} // end if
return has_room_to_add;
} // end add
template<class ItemType>
bool Set<ItemType>::Remove(const ItemType& an_entry)
{
int located_index = GetIndexOf(an_entry);
bool can_remove_item = !IsEmpty() && (located_index > -1);
if (can_remove_item)
{
item_count_--;
items_[located_index] = items_[item_count_];
} // end if
return can_remove_item;
} // end remove
template<class ItemType>
void Set<ItemType>::Clear()
{
item_count_ = 0;
} // end clear
template<class ItemType>
int Set<ItemType>::GetFrequencyOf(const ItemType& an_entry) const
{
int frequency = 0;
int search_index = 0;
while (search_index < item_count_)
{
if (items_[search_index] == an_entry)
{
frequency++;
} // end if
search_index++;
} // end while
return frequency;
} // end getFrequencyOf
template<class ItemType>
bool Set<ItemType>::Contains(const ItemType& an_entry) const
{
return GetIndexOf(an_entry) > -1;
} // end contains
template<class ItemType>
vector<ItemType> Set<ItemType>::ToVector() const
{
vector<ItemType> bag_contents;
for (int i = 0; i < item_count_; i++)
bag_contents.push_back(items_[i]);
return bag_contents;
} // end toVector
template<class ItemType>
int Set<ItemType>::GetIndexOf(const ItemType& target) const
{
bool found = false;
int result = -1;
int search_index = 0;
// if the bag is empty, item_count is zero, so loop is skipped
while (!found && (search_index < item_count_))
{
if (items_[search_index] == target)
{
found = true;
result = search_index;
}
else
{
search_index++;
} // end if
} // end while
return result;
} // end getIndexOf
*。h file
#ifndef TEACH_CSCI235_BAGADT_BAG_H_
#define TEACH_CSCI235_BAGADT_BAG_H_
#include "SetInterface.h"
template<class ItemType>
class Set : public SetInterface<ItemType>
{
public:
Set();
int GetCurrentSize() const;
bool IsEmpty() const;
bool Add(const ItemType& new_entry);
bool Remove(const ItemType& an_entry);
void Clear();
bool Contains(const ItemType& an_ntry) const;
int GetFrequencyOf(const ItemType& an_entry) const;
vector<ItemType> ToVector() const;
private:
static const int kDefaultSetSize_ = 6;
ItemType items_[kDefaultSetSize_]; // array of bag items
int item_count_; // current count of bag items
int max_items_; // max capacity of the bag
// Returns either the index of the element in the array items that
// contains the given target or -1, if the array does not contain
// the target.
int GetIndexOf(const ItemType& target) const;
}; // end Set
#include "Set.cpp"
#endif // TEACH_CSCI235_BAGADT_BAG_H_
我的输出是：
This is the empty set, and IsEmpty() returns 1
This set should have a single item, and a_set.Contains 1
This is the empty set, and IsEmpty() returns 1 The set is now empty and ready for values.
The Array should be size=4. Size = 6
Number 1 should be pressent in a_set. Return: 1
Number 3 should be pressent in a_set. Return: 1
Number 5 should be pressent in a_set. Return: 1
Number 10 should be pressent in a_set. Return: 1
1
0
42563728
1
2056807160
32767
42563728
我曾尝试在function.cpp中实现while循环和for循环（根据赋值）并且无法获得任何工作。你能否指出我正确的方向，因为我觉得我错过了什么。
感谢。
答案 0 :(得分：2)
更新到代码的完整列表后，似乎问题是使用数组范围之外的值（变量Array）。在C ++中，没有安全机制来阻止您访问未初始化的内存。
例如，给定以下代码段（改编自您的代码）：
int main(int, char**) {
/* Notice I only specify one element */
int array[] = { 1 };
int v = 0;
do {
std::cout << array[v] << std::endl;
v++;
} while (v < 7);
return 0;
}
我得到了这个输出：
rdahlgren@athas:~/work/cpp $ g++ main.cpp
rdahlgren@athas:~/work/cpp $ ./a.out
1
32767
0
3
4196544
0
372508672
＆＃39;奇怪＆＃39;这里的值来自未初始化的内存。其内容未定义。相反，您应该定义一个11元素数组。我说11个元素，因为你在代码中访问索引10，而C ++使用从零开始的数组索引。
如果我将我的代码段更新为：
int main(int, char**) {
/* Now I specify 11 elements */
int array[] = {
0, 1, 2, 3, 4, 5,
6, 7, 8, 9, 10
};
int v = 0;
do {
std::cout << array[v] << std::endl;
v++;
} while (v < 7);
return 0;
}
我得到以下（更理智）的结果：
rdahlgren@athas:~/work/cpp $ g++ main.cpp
rdahlgren@athas:~/work/cpp $ ./a.out
0
1
2
3
4
5
6
在C ++中使用变量之前，请务必初始化变量。如果不这样做会导致非常严重且难以发现错误。
为了进一步说明不同之处，这里有一个完整的示例，显示静态分配数组，然后在单独的步骤中初始化它。在上面的代码中，我使用数组文字语法来初始化它。
#include <iostream>
int main(int, char**) {
const unsigned int arrayLength = 5;
int array[arrayLength]; // <-- allocated, but uninitialized
std::cout << "Uninitialized values:\n";
for (int i = 0; i < arrayLength; ++i) {
std::cout << "Array index " << i << " is " << array[i] << std::endl;
}
// Now we can initialize it / insert values / whatever
for (int i = 0; i < arrayLength; ++i) {
array[i] = i * 10; // Times ten just for fun
}
for (int i = 0; i < arrayLength; ++i) {
std::cout << "Array index " << i << " is " << array[i] << std::endl;
}
}