variable or field "MergeSort" declared void?

[mothergoose729]

I am having trouble with this compiler error. If someone could help me fix it I would be grateful.

main.cpp

#include "MergeSort.h"
#include <iostream>
#include <cstdlib>

using namespace std;

int compare(const ItemType&, const ItemType&);

int main()
{
    const unsigned MAX = 10;
    ItemType a[MAX];
    
    for (unsigned i = 0; i < MAX; i++)
    {
        a[i] = rand()%2000;
    }
    MergeSort(a, MAX, compare);
    ItemType first = a[0];
        
    for (unsigned i = 1; i < MAX; i++)
    {
        ItemType next = a[i];
        if (next < first)
        {
            cout << "Error" << a[0] << " > " << a[i] << endl;
            first = next;
        }
    }
        
    return 0;
};

int compare (const ItemType& i1, const ItemType& i2)
{
    return int(i1-i2);
}
            

MergeSort.cpp

void MergeSort(ItemType* base, size_t nelem, 
                int(*fcmp)(const ItemType&, const ItemType&))
{
    if (nelem > 1)
    {
        size_t nelem1 = nelem/2;
        ItemType* base2 = base + nelem1;
        MergeSort(base, nelem1, fcmp);
        mergeSort(base2, nelem - nelem1, fcmp);
        merge(base, nelem, fcmp);
    }
}

void merge(ItemType* base, size_t nelem, 
            int(*fcmp)(const ItemType&, const ItemType&))
{
}

MergeSort.h

#include <cstdlib>

typedef float ItemType;

void MergeSort(ItemType*, size_t, int(*fcmp)(const ItemType&, const ItemType&));
            
            

Gives the following compiler error:

1. variable or field "MergeSort" declared void
1. 'ItemType' was not declared in this scope
1. 'base' was not declared in this scope
....

[Moschops]

When the compiler tries to compile the file named MergeSort.cpp, it has no idea whan an ItemType is. #include the header file that defines an ItemType.

[mothergoose729]

Its always something simple like that :p. Thank you. Marked as solved.

[vlad from moscow]

It looks like you forgot include the header in the cpp file.