16. Are Similar?

Task

Two arrays are called similar if one can be obtained from another by swapping at most one pair of elements in one of the arrays.

Given two arrays a and b, check whether they are similar.

Example

• For a = [1, 2, 3] and b = [1, 2, 3], the output should be
  areSimilar(a, b) = true.
  The arrays are equal, no need to swap any elements.

• For a = [1, 2, 3] and b = [2, 1, 3], the output should be
  areSimilar(a, b) = true.
  We can obtain b from a by swapping 2 and 1 in b.
  For a = [1, 2, 2] and b = [2, 1, 1], the output should be
  areSimilar(a, b) = false.
  Any swap of any two elements either in a or in b won’t make a and b equal.

Input/Output

• [execution time limit]
  4 seconds (py3)

• [input] array.integer a
  Array of integers.
  Guaranteed constraints: 3 ≤ a.length ≤ 105, 1 ≤ a[i] ≤ 1000.

• [input] array.integer b
  Array of integers of the same length as a.
  Guaranteed constraints: b.length = a.length, 1 ≤ b[i] ≤ 1000.

• [output] boolean
  true if a and b are similar, false otherwise.

My Solution

def areSimilar(a, b):
    i = 0
    fstIndx = -1
    sndIndx = -1
    while i < len(a):
        if a[i] != b[i]:
            fstIndx = i
            i += 1
            break
        i += 1
    while i < len(a):
        if a[i] != b[i]:
            sndIndx = i
            i += 1
            break
        i += 1
    while i < len(a):
        if a[i] != b[i]:
            return False
        i += 1
    if (fstIndx < 0 or sndIndx < 0):
        return True
    return (a[fstIndx] == b[sndIndx] and a[sndIndx] == b[fstIndx])