DaniWeb IT Discussion Community - View Single Post

Re: fibonacci

Oct 25th, 2007

Ok, I got it to work using a pointer. Here's my code.

 Help with Code Tags 
(Toggle Plain Text)
 Help with Code Tags 
 c++ Syntax (Toggle Plain Text) 
#include <ctime>
#include <iostream>
using namespace std ;
 
int fib ( int ) ;
 
int main ( )
{
    clock_t start ;
    clock_t end ;
 
    cout << "Beginning timer..." << endl ;
    start = clock() ;
 
    cout << endl ;
    for ( int k = 0 ; k < 12 ; k++ )
    {
    int i = fib ( k ) ;
    cout << i << "\t" ;
    }
 
    cout << endl ;
 
    end = clock() ;
    cout << "\nThe calculation took " << ( double ( end ) - start ) / CLOCKS_PER_SEC << " seconds.\n" ;
 
    cout << "\n\n-- Done --\n\n" ;
 
    return 0 ;
}
 
int fib ( int n )
{
    int * fibArray = new int[ n ] ;
 
    if ( n <= 1 )
        return 1 ;
    else
    {
        fibArray[ 0 ] = 1 ;
        fibArray[ 1 ] = 1 ;
 
        for ( int i = 2 ; i <= n ; i++ )
        fibArray [ i ] = ( fib ( n - 1 ) + ( fib ( n - 2 ) ) ) ;
 
    }
 
    return fibArray[ n ] ;
}
#include <ctime>
#include <iostream>
using namespace std ;

int fib ( int ) ;

int main ( )
{
    clock_t start ;
    clock_t end ;

    cout << "Beginning timer..." << endl ;
    start = clock() ;

    cout << endl ;
    for ( int k = 0 ; k < 12 ; k++ )
    {
    int i = fib ( k ) ;
    cout << i << "\t" ;
    }

    cout << endl ;

    end = clock() ;
    cout << "\nThe calculation took " << ( double ( end ) - start ) / CLOCKS_PER_SEC << " seconds.\n" ;

    cout << "\n\n-- Done --\n\n" ;

    return 0 ;
}

int fib ( int n )
{
    int * fibArray = new int[ n ] ;

    if ( n <= 1 )
        return 1 ;
    else
    {
        fibArray[ 0 ] = 1 ;
        fibArray[ 1 ] = 1 ;

        for ( int i = 2 ; i <= n ; i++ )
        fibArray [ i ] = ( fib ( n - 1 ) + ( fib ( n - 2 ) ) ) ;

    }

    return fibArray[ n ] ;
}
     Help with Code Tags   c++ Syntax (Toggle Plain Text)    #include <ctime>#include <iostream>using namespace std ; int fib ( int ) ; int main ( ){    clock_t start ;    clock_t end ;     cout << "Beginning timer..." << endl ;    start = clock() ;     cout << endl ;    for ( int k = 0 ; k < 12 ; k++ )    {    int i = fib ( k ) ;    cout << i << "\t" ;    }     cout << endl ;     end = clock() ;    cout << "\nThe calculation took " << ( double ( end ) - start ) / CLOCKS_PER_SEC << " seconds.\n" ;     cout << "\n\n-- Done --\n\n" ;     return 0 ;} int fib ( int n ){    int * fibArray = new int[ n ] ;     if ( n <= 1 )        return 1 ;    else    {        fibArray[ 0 ] = 1 ;        fibArray[ 1 ] = 1 ;         for ( int i = 2 ; i <= n ; i++ )        fibArray [ i ] = ( fib ( n - 1 ) + ( fib ( n - 2 ) ) ) ;     }     return fibArray[ n ] ;} #include <ctime>
#include <iostream>
using namespace std ;

int fib ( int ) ;

int main ( )
{
    clock_t start ;
    clock_t end ;

    cout << "Beginning timer..." << endl ;
    start = clock() ;

    cout << endl ;
    for ( int k = 0 ; k < 12 ; k++ )
    {
    int i = fib ( k ) ;
    cout << i << "\t" ;
    }

    cout << endl ;

    end = clock() ;
    cout << "\nThe calculation took " << ( double ( end ) - start ) / CLOCKS_PER_SEC << " seconds.\n" ;

    cout << "\n\n-- Done --\n\n" ;

    return 0 ;
}

int fib ( int n )
{
    int * fibArray = new int[ n ] ;

    if ( n <= 1 )
        return 1 ;
    else
    {
        fibArray[ 0 ] = 1 ;
        fibArray[ 1 ] = 1 ;

        for ( int i = 2 ; i <= n ; i++ )
        fibArray [ i ] = ( fib ( n - 1 ) + ( fib ( n - 2 ) ) ) ;

    }

    return fibArray[ n ] ;
}  

I can't get it to work with numbers >=12; it gives a system error that it failed unexpectedly. I'm guessing it's a stack issue, but is there a way around it? Is my program the best it can be (using recursion and arrays)?

Last edited by Duki; Oct 25th, 2007 at 1:44 am.

It is practically impossible to teach good programming style to students that have had prior exposure to Basic; as potential programmers they are mentally mutilated beyond hope of regeneration.

-Edsger Dijkstra