#include int main(void) { int i, j; int n, w[101]; int total = 0; int memo[10001] = {0}; scanf("%d", &n); for(i = 0;i < n;i++){ scanf("%d", &w[i]); total += w[i]; } for(j = 0;j < 100;j++){ memo[w[j]] = 1; for(i = 0;i < 10000;i++){ if(memo[i] == 1 && i + w[j] <= 10000){ memo[i + w[j]] = 1; } } } if(memo[total / 2] == 1){ printf("possible\n"); } else{ printf("impossible\n"); } return 0; }