Labs_test1 A - Fedya and Maths 欧拉定理
Description
Fedya studies in a gymnasium. Fedya's maths hometask is to calculate the following expression:
for given value of n. Fedya managed to complete the task. Can you? Note that given number n can be extremely large (e.g. it can exceed any integer type of your programming language).
Input
The single line contains a single integer n (0 ≤ n ≤ 10105). The number doesn't contain any leading zeroes.
Output
Print the value of the expression without leading zeros.
Sample Input
4
4
124356983594583453458888889
0
Hint
Operation x mod y means taking remainder after division x by y.
Note to the first sample:
思路:由欧拉定理:a,n互质,则a^ph(n)=1 (mod n)。
∑ i^n mod 5 = ∑ i^(n/ph(5) *ph(5) +n mod ph(5)) mod n
= ∑ (i^(k*ph(5))*(i^n mod ph(5)) mod n
= ∑ 1 * (i^ (n mod ph(5))mod n
以及用同余模求大数n mod ph(5)
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