Cost of Sweets
Medium Accuracy: 57.75% Submissions: 45 Points: 4

Jeny love Sweets so much. Now she is at famous restaurant and wants to eat M pieces of a particular sweet. Cost of nth sweet can only be determined by the determinant of matrix of order n x n, where n = 1 to M. The (i, j)th term of matrix is given as: A[i][j]= minimum(i, j) *(-1)((i-1)*n + (j-1)).
Matrix indexes starts with 1. The task is to find the cost of M sweets.

Example 1:

Input: M = 1
Output: 1
Explanation: Matrix of 1*1 is: |1|.
Determinant of matrix 1x1 = 1.
Cost of 1 sweet = 1.



Example 2:

Input: M = 2
Output: 0
Explanation: Matrix of 2*2 is:  |1 -1|
|1 -2|.
Determinant of matrix 2x2= -1.
Cost of 2 sweets  =
Cost of 1st sweet + Cost of 2nd sweet = 1 + -1 = 0.


You dont need to read input or print anything. Complete the function costOfSweets() which takes M as input parameter and returns the cost of M sweets.

Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)

Constraints:
1<= M <=106

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