Vasya collects coins: he has exactly one coin for every year from 1 to *n*. Naturally, Vasya keeps all the coins in his collection in the order in which they were released. Once Vasya's younger brother made a change — he took all the coins whose release year dated from *l* to *r* inclusively and put them in the reverse order. That is, he took a certain segment [*l*, *r*] and reversed it. At that the segment's endpoints did not coincide. For example, if *n* = 8, then initially Vasya's coins were kept in the order 1 2 3 4 5 6 7 8. If Vasya's younger brother chose the segment [2, 6], then after the reversal the coin order will change to 1 6 5 4 3 2 7 8. Vasya suspects that someone else could have spoilt the permutation after his brother. Help him to find that out. Check if the given permutation can be obtained from the permutation 1 2 ... *n* using exactly one segment reversal. If it is possible, find the segment itself.
The first line contains an integer *n* (1 ≤ *n* ≤ 1000) which is the number of coins in Vasya's collection. The second line contains space-separated *n* integers which are the spoilt sequence of coins. It is guaranteed that the given sequence is a permutation, i.e. it contains only integers from 1 to *n*, and every number is used exactly 1 time.
import math,sys;input=sys.stdin.readline;S=lambda:input().rstrip();I=lambda:int(S());M=lambda:map(int,S().split());L=lambda:list(M());mod1=1000000007;mod2=998244353

n = I()
new = [i for i in range(1,n+1)]
arr = L()
if arr==new:
    print(0,0)
    exit()

if arr[0]!=new[0] and arr[n-1]==new[n-1]:
    index = 0
    for i in range(1,n):
        if abs(arr[i]-arr[i-1])!=1:
            index = i
            break
    
    if arr[:index][::-1] + arr[index:] ==new:
        print(1,index)
    else:
        print(0,0)
        
    exit()
    
elif arr[0]==new[0] and arr[n-1]!=new[n-1]:
    index = 0
    for i in range(1,n):
        if abs(arr[i]-arr[i-1])!=1:
            index = i
            break
    
    if arr[:index] + arr[index:][::-1]==new:
        print(index+1,n)
    else:
        print(0,0)
    
    exit()

elif arr[0]!=new[0] and arr[n-1]!=new[n-1]:
    if arr[::-1]==new:
        print(1,n)
    else:
        print(0,0)
    
    exit()

else:
    t = 2
    pos = []
    for i in range(1,n):
        if abs(arr[i]-arr[i-1])!=1:
            pos.append(i)
            t-=1
    
    if t!=0:
        print(0,0)
    elif arr[:pos[0]] + arr[pos[0]:pos[1]][::-1] + arr[pos[1]:] ==new:
        print(pos[0]+1, pos[1])
    else:
        print(0,0)
    
    exit()