Fibonacci in the Pocket
Time Limit: 1 Second Memory Limit: 65536 KB
DreamGrid has just found a Fibonacci sequence and two integers and in his right pocket, where indicates the -th element in the Fibonacci sequence.
Please tell DreamGrid if is even or is odd.
Recall that a Fibonacci sequence is an infinite sequence which satisfies , and for all .
Input
There are multiple test cases. The first line of the input contains an integer (about 100), indicating the number of test cases. For each test case:
The first and only line contains two integers and (). Their meanings are described above.
Output
For each test case output one line. If is even output “0” (without quotes); If is odd output “1” (without quotes).
Sample Input
6
1 2
1 3
1 4
1 5
123456 12345678987654321
123 20190427201904272019042720190427
Sample Output
0
0
1
0
0
1
题意：
给你斐波那契数列下标a和b，求奇偶。
分析：
我们发现斐波那契数列的1 1 2 3 5 8 13
原本数组: 奇奇偶 奇奇偶 奇奇偶 奇奇偶
前缀和奇偶性： 奇偶偶 奇偶偶 奇偶偶 奇偶偶
所以只需要模3判断一下，奇-奇 偶-偶为偶数，其他为奇数。
import java.math.*;
import java.util.*;
public class Main {
public static void main(String[] args) {
BigInteger a,b;
BigInteger one = new BigInteger("1");
BigInteger two = new BigInteger("2");
BigInteger zero = new BigInteger("0");
BigInteger three= new BigInteger("3");
Scanner scanner=new Scanner(System.in);
int T=scanner.nextInt();
while((T--)!=0) {
a=scanner.nextBigInteger();
b=scanner.nextBigInteger();
a=a.subtract(new BigInteger("1"));
a=a.mod(three);
b=b.mod(three);
if((!a.equals(one)&&b.equals(one))||(a.equals(one)&&!b.equals(one)))
System.out.println("1");
else
System.out.println("0");
}
}
}