[Dev-C++] Invalid type argument of 'unary *'

[Kenneth P. R. <kpr...@op...>]

I'm getting error message "invalid type argument of 'unary *'" on the 
stmt indicated, and I just don't see why.  Couldja help?  I've clipped 
out what pertains to these variables.  TIA.
Ken



//    Functions
void Day1Hit(int &d1,  string &day2,  vector<string> &mtglist,  int 
&gsbegin,  int &gsend)    {
    cout << "Now in Day1Hit..." << endl;

    for (int i= *gsbegin; i < *gsend; i++)    {                        
      ERROR IS FOR THIS STMT

        if (*mtglist[i].substr(0,3) == *day2.substr(((*d1+1)*3)-3,3))    {
            cout << "Day1Hit: matched on " << (mtglist[i].substr(0,3) << 
endl;
            cout << *Day2.substr(((*d1+1)*3)-3,3)) << endl;
        }    // end if
    }    // end for
return;}    // end Day1Hit


vector<string> Mtglist;        // Input - loaded from a disk file
vector<int> Groupset;        // subscripts/pointers to Groupset ranges


{Here, Groupset is created during a first pass through Mtglist.
Groupset[n] is the beginning of a range of records in Mtglist to be 
processed.
Groupset[n+1] is the end of that range of records in Mtglist.
The last record in any range in Mtglist is called the WDR.}


Day1.assign("SMTWTFS");
Day2.assign("SunMonTueWedThuFriSat");

//    gs moves thru Groupset[].
for (int gs=0; gs < Groupset.size()-1; gs+=2)    {
   
    //    Process Day1 against the WDR.  d1 moves through Day1, looking 
for a hit.
    for (int d1=0; d1 < 7; d1++)    {
       
        //    I set the next variables for readability and ease of typing.
        D1P=Day1.substr(d1,1);
        WDRP=Mtglist[Groupset[gs+1]].substr(d1+1,1);      
       
        if (D1P == WDRP)    {
           
            int gsbegin=Groupset[gs];     // record number of beginning 
of a group range in Mtglist
            int gsend=Groupset[gs+1];    // record number of end of that 
group range in Mtglist
           
            Day1Hit(&d1,&Day2,&Mtglist,&gsbegin,&gsend);