Điểm:
400
Thời gian:
1.0s
Bộ nhớ:
256M
Input:
bàn phím
Output:
màn hình
A number is special if the sum of its digits is a prime number. Given an integer \(N\), count the number of positive integer
pairs \((x, y)\) where both \(x\) and \(y\) are special and \(x + 2y = N\).
Input
- The first line of input contains the one integer \(N (1 \le N \le 10^{15})\).
Output
- Output a single number, the number of satisfied pairs.
Example
Test 1
Input
100
Output
7
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