Fibonacci Numbers - Overclock.net

Mikey122687 · 10-31-09

PHP Code:


			
#include <iostream>
using namespace std;

// The function for finding the Fibonacci number
int fib(int);

int main()
{
  // Prompt the user to enter an integer
  cout <<  "Enter an index for the Fibonacci number: ";
  int index;
  cin >> index;

  // Display factorial
  cout << "Fibonacci number at index " << index << " is "
    << fib(index) << endl;

  return 0;
}

// The function for finding the Fibonacci number
int fib(int index)
{
  if (index == 0) // Base case
    return 0;
  else if (index == 1) // Base case
    return 1;
  else // Reduction and recursive calls
    return fib(index - 1) + fib(index - 2);
}

So i have that code, and i'm supposed to find the number of times the 'fib' function is called.

Any idea how to do that?

Error 404 · 10-31-09

Quote:

Originally Posted by Mikey122687

PHP Code:


			
#include <iostream>
using namespace std;

// The function for finding the Fibonacci number
int fib(int);
int num = 0;

int main()
{
  // Prompt the user to enter an integer
  cout <<  "Enter an index for the Fibonacci number: ";
  int index;
  cin >> index;

  // Display factorial
  cout << "Fibonacci number at index " << index << " is "
    << fib(index) << endl;

 //Display # of times fib() is called
cout <<"Fib() called " << num << " times.";
  return 0;
}

// The function for finding the Fibonacci number
int fib(int index)
{
  num++;
  if (index == 0) // Base case
    return 0;
  else if (index == 1) // Base case
    return 1;
  else // Reduction and recursive calls
    return fib(index - 1) + fib(index - 2);
}

So i have that code, and i'm supposed to find the number of times the 'fib' function is called.

Any idea how to do that?

It creates another variable (num) and increments it once every time fib() is called.

That should do it. My C/C++ is a bit rusty...

edit: forgot ";'s"

edit 3, maybe 4 or 5: Added .exe

serge2k · 10-31-09

that will work.

then just print num after the call.

Absolutely horrible way to calculate fibonacci numbers though. very wasteful. As you shall see.

chatch15117 · 10-31-09

have fib increment a global variable at the beginning of each function call.

Mikey122687 · 11-01-09

Quote:

Originally Posted by Error 404

It creates another variable (num) and increments it once every time fib() is called.

That should do it. My C/C++ is a bit rusty...

edit: forgot ";'s"

edit 3, maybe 4 or 5: Added .exe

Can you post the code? I don't need the program, i just need to know how to do it

Quote:

Originally Posted by serge2k

that will work.

then just print num after the call.

Absolutely horrible way to calculate fibonacci numbers though. very wasteful. As you shall see.

Why is this a bad way to do it?

Quote:

Originally Posted by chatch15117

have fib increment a global variable at the beginning of each function call.

what do you mean? how would i do that?

Error 404 · 11-01-09

I edited the code in your quotes

It works, too. Bonus!

Blizzie · 11-01-09

Code:

	if (n == 0 || n == 1){
		return 1;
	}
	else {
		sum = (Fib(n-1) + Fib(n-2));
		return sum;
	}

You want this as a recursive function that calls itself.

chatch15117 · 11-01-09

Quote:

Originally Posted by Mikey122687

Can you post the code? I don't need the program, i just need to know how to do it

Why is this a bad way to do it?

what do you mean? how would i do that?

Quote:

#include <iostream>
using namespace std;

// The function for finding the Fibonacci number
int fib(int);

int main()
{
// Prompt the user to enter an integer
cout << "Enter an index for the Fibonacci number: ";
int index;
cin >> index;
int RAWR = 0;
// Display factorial
cout << "Fibonacci number at index " << index << " is "
<< fib(index) << endl;

return 0;
}

// The function for finding the Fibonacci number
int fib(int index)
{
if (index == 0) // Base case
return 0;
else if (index == 1) // Base case
return 1;
else // Reduction and recursive calls
{
RAWR++;
return fib(index - 1) + fib(index - 2);
}
}

like that?

Mikey122687 · 11-01-09

PHP Code:


			
#include <iostream>
using namespace std;

int count = 0;
// The function for finding the Fibonacci number
int fib(int);


int main()
{
  // Prompt the user to enter an integer
  cout <<  "Enter an index for the Fibonacci number: ";
  int index;
  cin >> index;

  // Display factorial
  cout << "Fibonacci number at index " << index << " is "
    << fib(index) << endl;

  // Display how many times the function 'fib' is called
  cout << "The Function 'fib' is called " << count << " times" << endl;
  return 0;
}

// The function for finding the Fibonacci number
int fib(int index)
{
  if (index == 0) // Base case
    return 0;
  else if (index == 1) // Base case
    return 1;
  else // Reduction and recursive calls
  {
    count++;
    return fib(index - 1) + fib(index - 2);
  }
}

here is what i have so far