HDU 5351 MZL's Border

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Problem Description
As is known to all, MZL is an extraordinarily lovely girl. One day, MZL was playing with her favorite data structure, strings.

MZL is really like Fibonacci Sequence, so she defines Fibonacci Strings in the similar way. The definition of Fibonacci Strings is given below.
  
  1) fib1=b
  
  2) fib2=a
  
  3) fibi=fibi1fibi2, i>2
  
For instance, fib3=ab, fib4=aba, fib5=abaab.

Assume that a string s whose length is n is s1s2s3...sn. Then sisi+1si+2si+3...sj is called as a substring of s, which is written as s[i:j].

Assume that i<n. If s[1:i]=s[ni+1:n], then s[1:i] is called as a Border of s. In Borders of s, the longest Border is called as sLBorder. Moreover, s[1:i]'s LBorder is called as LBorderi.

Now you are given 2 numbers n and m. MZL wonders what LBorderm of fibn is. For the number can be very big, you should just output the number modulo 258280327(=2×317+1).

Note that 1T100, 1n103, 1m|fibn|.
 

Input
The first line of the input is a number T, which means the number of test cases.

Then for the following T lines, each has two positive integers n and m, whose meanings are described in the description.
 

Output
The output consists of T lines. Each has one number, meaning fibn's LBorderm modulo 258280327(=2×317+1).
 

Sample Input
24 35 5
 

Sample Output
12
找找规律,然后模拟一下,注意有大数
import java.io.*;import java.math.BigInteger;import java.util.*;public class Main{    public static void main(String args[])    {        Scanner cin = new Scanner(System.in);            BigInteger f[][] = new BigInteger[1005][3];        int i;        f[0][1]=BigInteger.ZERO;        f[0][2]=BigInteger.ZERO;        f[1][1]=BigInteger.ZERO;        f[1][2]=BigInteger.ZERO;        f[0][0]=BigInteger.ONE;        f[1][0]=BigInteger.ONE;        for (i=2;i<=1000;i++)        {            f[i][0]=f[i-1][0].add(f[i-2][0]);            f[i][1]=f[i-1][2].subtract(f[i-1][1]);            f[i][2]=f[i][1].add(f[i][0]).subtract(BigInteger.ONE);        }        int T=cin.nextInt();        for(;T>=1;T--)        {            int n;            BigInteger m;            n=cin.nextInt();            m=cin.nextBigInteger();            for(i=1;i<=1000;i++)            {              if(m.compareTo(f[i][0])<1)              {                  m=f[i][1].add(m).subtract(BigInteger.ONE);                  m=m.mod(BigInteger.valueOf(258280327));                  System.out.println(m);                  break;              }              else                  m=m.subtract(f[i][0]);            }        }    }}


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