# 24090번
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10**5)

def quick_sort(arr,p,r):
    if p < r:
        q = partition(arr,p,r)
        quick_sort(arr, p, q - 1)   
        quick_sort(arr, q + 1, r)   

def partition(arr,p,r):
    global cnt
    x = arr[r]
    i = p - 1
    for j in range(p,r):
        if arr[j] <= x:
            i += 1
            arr[i],arr[j] = arr[j],arr[i]
            cnt += 1
            if cnt == K:
                print(arr[i],arr[j])
                sys.exit(0)
    if i + 1 != r:
        arr[i + 1],arr[r] = arr[r],arr[i + 1]
        cnt += 1
        if cnt == K:
            print(arr[i+1],arr[r])
            sys.exit(0)
    return i + 1

N,K = map(int,input().split())
A = list(map(int,input().split()))

cnt = 0
quick_sort(A,0,N-1)
if K > cnt:
    print(-1)