0

I have some errors LNK2019 with my homework, but I can't solve it.

My error

Error 7 error LNK2019: unresolved external symbol "void __cdecl input(int * &,int &,class std::basic_ifstream<char,struct std::char_traits<char> > &)" (?input@@YAXAAPAHAAHAAV?$basic_ifstream@DU?$char_traits@D@std@@@std@@@Z) referenced in function _main E:\Ex\Bai_1_No_File\main.obj Bai_1_No_File

This is my code.

main.cpp

```
#include "function.h"
#include <conio.h>
#include <fstream>
#pragma comment
void main()
{
int* pi=NULL;
int n;
bool t=true;
ifstream fin("in.txt");
ofstream fou("out.txt");
while (t==true)
{
system("cls");
cout<<" 1 . input an array"<<endl;
cout<<" 2 . print an array"<<endl;
cout<<" 3 . find an integer"<<endl;
cout<<" 4 . print an ascending array"<< endl;
cout<<" 5 . exit"<< endl;
int z;
cout<<" your selection : ";
cin>>z;
if (z<1 || z>5)
{
cout<<"Your selection is wrong. Please press anykey to try again!!!";
fou<<"Your selection is wrong. Please press anykey to try again!!!"<<endl;
getch();
}
else
if (z==5)
{
t=false;
}
else
if (pi==NULL && z!=1)
{
cout<<"There is't an array in the memory please input"<<endl;
fou<<"There is't an array in the memory please input"<<endl;
cout<<"Press anykey to continue";
getch();
}
else
{
switch (z)
{
case 1:
{
input(pi,n,fin); // read from file
break;
}
case 2:
{
print(pi, n,fou);
getch();
break;
}
case 3:
{
int x;
if (findNumber(pi,n,x)==true)
{
cout<<"Yes"<<endl;
cout<<"integers bigger : "<<endl;
fou<<"Yes"<<endl;
fou<<"integers bigger : "<<endl;
printIntBigger(pi,n,x);
}
else
{
cout<<"No"<<endl;
fou<<"No"<<endl;
}
getch();
break;
}
case 4:
{
printIntAscending(pi,n);
print(pi,n,fou);
getch();
break;
}
}
}
}
if (pi!=NULL)
{
delete []pi;
}
fou.close();
};
```

function.h

```
#ifndef _HAM_
#define _HAM_
#include <fstream>
#include <iostream>
using namespace std;
void input(int* &pi, int& n, ifstream &fin);
void print(int* pi,int n, ofstream &fou);
bool findNumber(int* pi,int n, int& x);
void printIntBigger(int* pi,int n,int x);
void swap(int& x, int& y);
void printIntAscending(int* pi,int n);
#endif
```

function.cpp

```
#include "function.h"
void input(int* &pi,int& n, fstream &fin)
{
if (pi!=NULL)
{
delete pi;
}
fin>>n;
pi = new int[n];
if (pi[0]!=NULL)
{
for (int i=0; i<n; i++)
{
fin>>pi[0];
}
}
fin.close();
};
void print(int* pi, int n, fstream &fou)
{
for (int i=0; i<n; i++)
{
cout<<pi[i]<<" ";
fou<<pi[i]<<" ";
}
fou<<endl;
};
bool findNumber(int* pi,int n, int& x)
{
cout<<"input an integer : ";
cin>>x;
for (int i=0; i<n; i++)
{
if (pi[i]==x)
return true;
}
return false;
};
void printIntBigger(int* pi,int n,int x)
{
for (int i=0; i<n ; i++)
{
if (pi[i]>x)
cout<<pi[i]<<" ";
}
};
void swap(int& x, int& y)
{
int t;
t=x;
x=y;
y=t;
};
void printIntAscending(int* &pi,int n)
{
int i=0;
while (i<n-1)
{
i=0;
for(int j=0; j<n-1; j++)
{
if (pi[j]>pi[j+1])
swap(pi[j],pi[j+1]);
else
i++;
}
}
};
```