[UVa] 10183 - How Many Fibs?

題目網址: http://goo.gl/QL323o

題意:
(from luckycat)


解法: 大數運算直接找。

TAG: BigNum

注意:

程式碼:

	/**
	* Tittle: 10183 - How Many Fibs?
	* Author: Cheng-Shih, Wong
	* Date: 2015/05/09
	*/
	import java.util.*;
	import java.math.*;
	public class Main {
	public static void main( String[] args ) {
	Scanner input = new Scanner( System.in );
	BigInteger[] fibs = new BigInteger[505];
	String sa, sb;
	BigInteger a, b;
	int cnt;
	fibs[0] = fibs[1] = BigInteger.ONE;
	for( int i=2; i <= 500; ++i )
	fibs[i] = fibs[i-1].add(fibs[i-2]);
	while( input.hasNext() ) {
	sa = input.next();
	sb = input.next();
	if( sa.equals("0") && sb.equals("0") )
	break;
	a = new BigInteger( sa );
	b = new BigInteger( sb );
	cnt = 0;
	for( int i=1; i <= 500; ++i ) {
	if( fibs[i].compareTo(a)>=0 && fibs[i].compareTo(b)<=0 )
	++cnt;
	}
	System.out.println(cnt);
	}
	input.close();
	}
	}

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