Problem : Mountain peak sequence Consider the first three natural numbers 1, 2, 3. These can be arranged in the following ways: 2, 3, 1 and 1, 3, 2. Inboth of these arrangements, the numbers increase to a certain point and then decrease. A sequence with this property is called a "mountain peak sequence". Given an integer N, write a program to find the remainder of mountain peak arrangements that can be obtained by rearranging the numbers 1, 2, ...., N. Input Format: One line containing the integer N Output Format: An integer m, giving the remainder of the number of mountain peak arrangements that could be obtained from 1, 2, ...., N is divide by Mod Constraints : Mod = 109+7 N ≤ 109 Example 1 Input 3 Output 2 Explanation There are two such arrangements: 1, 3, 2 and 2, 3, 1 Example 2 Input 4 Output 6 Explanation The six arrangements are (1, 2, 4, 3), (1,3,4,2), (1,4,3,2), (2,3,4,1), (2,4,3,1), (3,4,2,1) Note: Please do not use packag...
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