PROGRAM FOR Fibonacci numbers

Here is the slightly modified version of the previous program, which is flexible to find the Fibonacci numbers between the given range.

Logic:  Fibonacci numbers are the the members of the Fibonacci series, which grows up accord to Fibonacci rule. The rule states, the present number in the series is the sum of past number and and the number before past, with the initial condition that, series starts from 0, and the second term is  1. Mathematically,

   F(n+1) = F(n) + F(n-1)           // F(1) =0 and F(2) = 1

Taking the upper and lower limit from the user, tracing the Fibonacci series with a while loop, finding the present Fibonacci member and printing that only if the same falls under the user specified range.

#include<stdio.h>
void main()
{
     int lim_up, lim_low, A=0, B=1, C;
     clrscr();
     printf("\n\n\t ENTER THE LOWER LIMIT...: ");
     scanf("%d", &lim_low);
     printf("\n\n\t ENTER THE UPPER LIMIT...: ");
     scanf("%d", &lim_up);
     printf("\n\n\t FIBONACCI NUMBERS ARE...: ");
     while(A<lim_up)
     {
          if(A>lim_low)
          printf("\n\n\t\t\t%d", A);
          C = A + B;
          A = B;
          B = C;
     }
     getch();
}

Download exe and source code here.

Related source codes :
 

      Program to find the fibonacci numbers below a given number.

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