POJ 2413 How many Fibs?

文章目錄

• Time Limit: 1000MS
•  
• Memory Limit: 65536K
• Total Submissions: 10081
•  
• Accepted: 3733

How many Fibs?

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 10081		Accepted: 3733

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<=10100. 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

import java.util.*;import java.io.*;import java.math.BigInteger;public class Main{public static void main(String[] args) {Scanner sc=new Scanner(new BufferedInputStream(System.in));while(sc.hasNextBigInteger()){BigInteger a=sc.nextBigInteger();BigInteger b=sc.nextBigInteger();if(a.compareTo(BigInteger.ZERO)==0&&b.compareTo(BigInteger.ZERO)==0){break;}BigInteger big[]=new BigInteger[1000000];int count=0;big[1]=BigInteger.valueOf(1);big[2]=BigInteger.valueOf(2);for(int i=1;i<big.length;i++){if(i>2){big[i]=big[i-1].add(big[i-2]);}if((big[i].compareTo(a)>=0)&&(big[i].compareTo(b)<=0)){count++;}if(big[i].compareTo(b)==1){break;}}System.out.println(count);}}}