对链表打印函数的未定义引用

Question

我编写了一个小程序，它接受用户输入并创建一个链表。我遇到了一个错误，当建筑似乎涉及到传递到打印函数的头指针。错误如下:

undefined reference to `PrintList(PetData*)'|
||=== Build failed: 1 error(s), 0 warning(s) (0 minute(s), 0 second(s)) ===|

如果有人可以指出(不是有意的)我在正确的方向，甚至明确地给我一个修复，我将非常感激。源代码:

#include <iomanip>
#include <string>
#include <iostream>

using namespace std;
struct PetData{
    int IdNumber;
    string PetType;
    PetData *link;
};
PetData * HeadPointer=NULL;
void InsertItem(int, string, PetData*);
void PrintList(PetData*);
int main(){
    int init_IdNumber;
    string init_PetType;
    PetData * CRP = NULL;
    char cflag = 'Y';
    while (toupper(cflag) == 'Y'){
        cout << "Please Enter an ID Number: " << endl;
        cin >> init_IdNumber;
        cout << "Please Enter a Pet Type: " << endl;
        cin >> init_PetType;
        CRP = new PetData;
        InsertItem(init_IdNumber,init_PetType,CRP);
        HeadPointer=CRP;
        cout << "Would you like to enter another? (Y/N)" << endl;
        cin >> cflag;

    };

    PrintList(HeadPointer);

    return 1;
};
void InsertItem(int init_IdNumber, string init_PetType, PetData* CRP){
    CRP->PetType = init_PetType;
    CRP->IdNumber = init_IdNumber;
    CRP->link = HeadPointer;
};
void PrintList(){
    while(HeadPointer != NULL){
        cout << HeadPointer->PetType << "t" << HeadPointer->IdNumber << endl;
        HeadPointer = HeadPointer->link;
    }
};

在任何人提到它之前，这不是家庭作业。这是我的教授建议我们独立创作的东西，为将来的期中作业做准备。

谢谢!

Answer 1

函数声明和定义不匹配

函数的原型为void PrintList(PetData*);，定义是void PrintList()。这就是不匹配的原因。

有正确的代码

void PrintList(PetData* HeadPointer){
    while(HeadPointer != NULL){
        cout << HeadPointer->PetType << "t" << HeadPointer->IdNumber << endl;
        HeadPointer = HeadPointer->link;
    }