A. Exam

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

An exam for n students will take place in a long and narrow room, so the students will sit in a line in some order. The teacher suspects that students with adjacent numbers (i and i + 1) always studied …

C - C

**Time Limit:**1000MS **Memory Limit:**262144KB 64bit IO Format:%I64d & %I64u

Submit Status

Description

Permutation_p_ is an ordered set of integers _p_1,   p_2,   …,   p__n, consisting of n distinct positive integers not larger than n. We’ll denote as_n the length of permutation _p_1,   _p_2, …