ArithmeticSubarrays.py

# A sequence of numbers is called arithmetic if it consists of at least two elements, and the difference between every two consecutive elements is the same. More formally, a sequence s is arithmetic if and only if s[i+1] - s[i] == s[1] - s[0] for all valid i.
# For example, these are arithmetic sequences:
#   1, 3, 5, 7, 9
#   7, 7, 7, 7
#   3, -1, -5, -9
# The following sequence is not arithmetic:
#   1, 1, 2, 5, 7
# You are given an array of n integers, nums, and two arrays of m integers each, l and r, representing the m range queries, where the ith query is the range [l[i], r[i]]. All the arrays are 0-indexed.
# Return a list of boolean elements answer, where answer[i] is true if the subarray nums[l[i]], nums[l[i]+1], ... , nums[r[i]] can be rearranged to form an arithmetic sequence, and false otherwise.

def checkArithmeticSubarrays(nums, l, r):
    output = []

    for i in range(len(l)):
        subarray = nums[l[i]:r[i] + 1]
        subarray.sort()
        diff = subarray[0] - subarray[1]

        for x in range(1, len(subarray) - 1): 
            if subarray[x] - subarray[x + 1] != diff:
                output.append(False)
                break 
        
        if len(output) <= i: 
            output.append(True)
    
    return output

# Test cases
nums = [4,6,5,9,3,7]
l = [0,0,2]
r = [2,3,5]
print(checkArithmeticSubarrays(nums, l, r))

nums = [-12,-9,-3,-12,-6,15,20,-25,-20,-15,-10]
l = [0,1,6,4,8,7]
r = [4,4,9,7,9,10]
print(checkArithmeticSubarrays(nums, l, r))