Re: Function Declaration in g++

[BobR]

<derrick_chi@msn.com> wrote in message...
>   Hello guys
>      I am new to this forum and to gcc/g++ and I need to know exactly
> how to declare a function in g++.

Your code shows signs of an 'C' programmer. I'll make some suggestions
(which might help you find the real problem).

>
#include <iostream>  //  #include "iostream"
#include <iomanip>  //  #include "iomanip"
// unused  #include <cmath>       //  #include "math.h"
>
> using namespace std;
Not 'bad', but, not good. <G>

>
> unsigned int GCD_FUNCT( unsigned int,  unsigned int );
>
> int main() {
>
>    unsigned int ARRAY[32], GCD[16];

Any chance you could use 'std::vector' here? (see below)
     // std::vector<unsigned> Array( 32 );
     // std::vector<unsigned> Gcd( 32 );

// >    unsigned int Loop_Control_V, Reg1, Reg2, new_value;

In C++, you don't need to declare all your vars at the top. Put them as
close to use as possible (and initialize them).

>
>   for ( unsigned int i = 0; i < 31; ++ i ) {
>
// >         new_value = i + ( 3 * (4) );
          // 'new_value' not used outside this loop, so:
          unsigned int new_value( i + ( 3 * (4) ) );
>
>           if ( new_value % 2 != 0 ) {
// >                new_value = new_value * 4;
                 new_value *= 4;  // another way to write the above
>                }
>           else{
// >                  new_value = new_value * 10;
                  new_value *= 10;
>                  }
>          ARRAY[i] = new_value;
>          } // for(i)
>
// >      Loop_Control_V = 0;
     unsigned int Loop_Control_V(0);
     unsigned int Reg1(0), Reg2(0);
>
>           while ( Loop_Control_V < 30 ){
>                 if( ARRAY[Loop_Control_V] >
>                              ARRAY[Loop_Control_V + 1] ) {
>                      Reg1 = ARRAY[Loop_Control_V];
>                      Reg2 = ARRAY[Loop_Control_V + 1];
>                      }
>                 else {
>                      Reg1 = ARRAY[Loop_Control_V + 1];
>                      Reg2 = ARRAY[Loop_Control_V];
>                      }
>

>           GCD[Loop_Control_V] = GCD_FUNCT(Reg1,Reg2);

BZZzzzzt!!! GCD is only [16], Loop_Control_V is going to 29!

// >           Loop_Control_V = Loop_Control_V + 1;
          ++Loop_Control_V;
>           } // while(Loop_Control_V)
>
>   return 0;
>  } // main()
>
>  unsigned int GCD_FUNCT( unsigned int REGa,  unsigned int REGb){
// >  unsigned int temp1, temp2, GCD;
// >      temp1 = REGa;
// >      temp2 = REGb;
     unsigned int temp1( REGa ), temp2( REGb );

>      while ( temp1 != temp2 ) {
>            if ( temp1 > temp2 ) {
// >                 temp1 = temp1 - temp2;
                temp1 -= temp2;
>                 }
>            else{
// >                 temp2 = temp2 - temp1;
                temp2 -=temp1;
>                 }
>            } // while(temp1)
// >      GCD = temp1;
// >   return GCD;

    return  temp1;

>  } // GCD_FUNCT(unsigned unsigned)
>


// - using vectors -
#include <iostream>
#include <vector>
#include <iterator>      // stream_iterator
#include <algorithm>     // copy

unsigned int GCD_FUNCT( unsigned int REGa,  unsigned int REGb){
     while( REGa != REGb ){
          if( REGa > REGb ){ REGa -= REGb;}
          else{ REGb -= REGa; }
          } // while(REGa)
     return REGa;
     } // GCD_FUNCT(unsigned unsigned)

int main(){
     std::vector<unsigned> Array( 32 );
     std::vector<unsigned> Gcd( 32 );

     for( unsigned int i(0); i < Array.size(); ++ i ){
          Array.at( i ) = i + ( 3 * 4 );
          if( Array.at( i ) % 2 != 0 ) {  Array.at( i ) *= 4; }
          else{  Array.at( i ) *= 10; }
          } // for(i)

     unsigned int Loop_Control_V(0);
     while ( Loop_Control_V < 30 ){
          if( Array.at( Loop_Control_V ) >
                         Array.at( Loop_Control_V + 1 ) ){
               Gcd.at( Loop_Control_V ) =
                         GCD_FUNCT( Array.at( Loop_Control_V ),
                                   Array.at( Loop_Control_V + 1 ) );
               } // if(>)
          else{
               Gcd.at( Loop_Control_V ) =
                         GCD_FUNCT( Array.at( Loop_Control_V + 1 ),
                                   Array.at( Loop_Control_V ) );
               } // else{<}
          ++Loop_Control_V;
          } // while(Loop_Control_V)

     std::copy( Gcd.begin(), Gcd.end(),
               std::ostream_iterator<unsigned int>( std::cout, " " ) );
               // alt: std::ostream_iterator<unsigned int>( std::cout,
"\n" ) );
     std::cout<<std::endl;

     return 0;
     } // main()

--
Bob R
POVrookie