Chapter 5,Problem c: Let Us C by Yashawant Kanetkar Solution Manual

Problem Statement:

Write a recursive function to obtain the first 25 numbers of a
Fibonacci sequence. In a Fibonacci sequence the sum of two
successive terms gives the third term. Following are the first
few terms of the Fibonacci sequence:
1 1 2 3 5 8 13 21 34 55 89...

Solution:

//Ahmad Furqan

//P5.c

#include <iostream>

#include <conio.h>

using namespace std;

int fabb[25],index=0;

void fabb_rec(int a, int b)

{

if (index == 25)

return;

fabb[index] = a + b; //add previous terms

//update last two terms

a = b;

b = fabb[index];

index++;

return fabb_rec(a, b);

}

void main(void)

{

cout << "First 25 numbers of a Fibnocci sequence are: " << endl;

index = 2;

fabb[0] = 1;

fabb[1] = 1;

fabb_rec(1, 1);

for (int i = 0; i < 25; i++)

cout << " " << fabb[i];

_getch();

}