杭电1316（How Many Fibs?）

点击打开杭电1316

Problem Description

Recall the definition of the Fibonacci numbers:
f1 := 1
f2 := 2
fn := fn-1 + fn-2 (n >= 3)

Given two numbers a and b, calculate how many Fibonacci numbers are in the range [a, b].

 

 

Input

The input contains several test cases. Each test case consists of two non-negative integer numbers a and b. Input is terminated by a = b = 0. Otherwise, a <= b <= 10^100. The numbers a and b are given with no superfluous leading zeros.

 

 

Output

For each test case output on a single line the number of Fibonacci numbers fi with a <= fi <= b.

 

 

Sample Input

10 1001234567890 98765432100 0

 

 

Sample Output

54

 

代码实现

import java.math.BigInteger;import java.util.Scanner;class Main{    public static void main(String[] args){        Scanner sc = new Scanner(System.in);        BigInteger[] fib=new BigInteger[1005];        fib[1]=BigInteger.valueOf(1);        fib[2]=BigInteger.valueOf(2);        for(int i=3;i<1005;i++){        fib[i]=fib[i-1].add(fib[i-2]);        }        int numb;        while(sc.hasNextBigInteger()){        BigInteger a=sc.nextBigInteger();            BigInteger b=sc.nextBigInteger();            if(a.equals(BigInteger.valueOf(0))&&b.equals(BigInteger.valueOf(0))){            break;            }        numb=0;            for(int i=1;i<1005;i++){            if(fib[i].compareTo(a)>=0&&fib[i].compareTo(b)<=0){            numb++;            }            if(fib[i].compareTo(b)>0){            break;            }            }            System.out.println(numb);        }    }}