import bisect import copy import decimal import fractions import heapq import itertools import math import random import sys from collections import Counter, deque,defaultdict from functools import lru_cache,reduce from heapq import heappush,heappop,heapify,heappushpop,_heappop_max,_heapify_max def _heappush_max(heap,item): heap.append(item) heapq._siftdown_max(heap, 0, len(heap)-1) def _heappushpop_max(heap, item): if heap and item < heap[0]: item, heap[0] = heap[0], item heapq._siftup_max(heap, 0) return item from math import gcd as GCD read=sys.stdin.read readline=sys.stdin.readline readlines=sys.stdin.readlines N,*W=map(int,read().split()) dp=[False]*(10**4+1) dp[0]=True for w in W: for i in range(10**4,w-1,-1): if dp[i-w]: dp[i]=True print(dp) s=sum(W) if s%2==0 and dp[s//2]: ans='possible' else: ans='impossible' print(ans)