int Flag(int Count_, char* S1_, char* S2_, int i, int j)
{
    int Result = 0;
    if ((i + Count_ <= strlen(S1_)) && (j + Count_ <= strlen(S2_)))
    {
        if (S1_[i+Count_] == S2_[j+Count_])
        {
            Result = 1;
        }
    }
    return Result;
}

// translated from Pascal.
// Source: http://delphikingdom.com/asp/viewitem.asp?catalogid=1147
int CompareStrings(char* S1, char * S2, int MatchCount, int * NCount)
{
    int Count_;
    int Count = 0;
    *NCount = 0;

    if(!strlen(S1) || !strlen(S2))
    {
        *NCount = 255;
        return 0;
    }

    int i = 1;
    do
    {
        int j = 1;
        do
        {
            if(S1[i] == S2[j])
            {
                Count_ = 1;
                while(Flag(Count_, S1, S2, i, j)) ++Count_;
                i = i + Count_ - 1;
                j = j + Count_ - 1;
                if (Count_ >= MatchCount) Count = Count + Count_;
            }
            ++j;
        }
        while(j < strlen(S2));
        ++i;
    }
    while(i < strlen(S1));

    if (strlen(S1) < strlen(S2))
        Count_ = strlen(S1);
    else
        Count_ = strlen(S2);

    *NCount = Count_ - Count;
    return Count;
}