1965. Fermat's Christmas Theorem

单点时限: 2.0 sec

内存限制: 256 MB

In a letter dated December 25, 1640; the great mathematician Pierre de Fermat wrote to Marin Mersenne that he just proved that an odd prime p is expressible as p = a2 + b2 if and only if p is expressible as p = 4c + 1. As usual, Fermat didn’t include the proof, and as far as we know, never wrote it down. It wasn’t until 100 years later that no one other than Euler proved this theorem. To illustrate, each of the following primes can be expressed as the sum of two squares:

5 = 2^2 + 1^2 13 = 3^2 + 2^2 17 = 4^2 + 1^2 41 = 5^2 + 4^2

Whereas the primes 11, 19, 23, and 31 cannot be expressed as a sum of two squares. Write a program to count the number of primes that can be expressed as sum of squares within a given interval.

输入格式

Your program will be tested on one or more test cases. Each test case is specified on a separate input line that specifies two integers L, U where L ≤ U < 1,000,000.

The last line of the input file includes a dummy test case with both L = U = −1.

输出格式

For each test case, write the result using the following format:

L U x y

where L and U are as specified in the input. x is the total number of primes within the interval [L, U] (inclusive), and y is the total number of primes (also within [L, U]) that can be expressed as a sum of squares.

样例

Input
10 20
11 19
100 1000
-1 -1
Output
10 20 4 2
11 19 4 2
100 1000 143 69

6 人解决,11 人已尝试。

6 份提交通过,共有 28 份提交。

7.6 EMB 奖励。

创建: 16 年前.

修改: 6 年,7 月前.

最后提交: 9 月,2 周前.

来源: Arab and North Africa 2007

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