hackerrank-almostSorted

#!/bin/python3

import math
import os
import random
import re
import sys

#
# Complete the 'almostSorted' function below.
#
# The function accepts INTEGER_ARRAY arr as parameter.
#
def is_sorted(arr):
    return all(arr[i] <= arr[i+1] for i in range(len(arr)-1))

def almostSorted(arr):
    # Write your code here
    # check swap
    swap_l, swap_r = -1, -1
    
    for i in range(1, len(arr)):
        if arr[i-1] > arr[i]:
            swap_l = i-1
            break
    for i in range(swap_l+1, len(arr)):
        if i == len(arr)-1 or arr[i+1] > arr[swap_l]:
            swap_r = i
            # print(arr, arr[swap_l], arr[swap_r])
            arr[swap_l], arr[swap_r] = arr[swap_r], arr[swap_l]
            # print(arr)
            break
            
    if is_sorted(arr):
        print("yes")
        print("swap", swap_l+1, swap_r+1)
        return
    # check reverse
    arr[swap_l], arr[swap_r] = arr[swap_r], arr[swap_l]
    # print("restore", arr)
    rev_l, rev_r = -1, -1
    for i in range(len(arr)-1):
        if rev_l == -1 and arr[i] > arr[i+1]:
            rev_l = i
        elif rev_l != -1 and arr[i] < arr[i+1]:
            rev_r = i
            break
    # print(rev_l, rev_r, arr)
    rev_sub = arr[rev_l: rev_r+1]
    # print(rev_sub)
    arr = arr[:rev_l] + rev_sub[::-1] + arr[rev_r+1:]
    # print(arr)
    
    if is_sorted(arr):
        print("yes")
        print("reverse", rev_l+1, rev_r+1)
        return
    print("no")
    
    
if __name__ == '__main__':
    n = int(input().strip())

    arr = list(map(int, input().rstrip().split()))

    almostSorted(arr)