// unsolved #include using namespace std; typedef long long ll; ll INF = 1LL << 60; int main() { int n; cin >> n; vector w(n + 1); for (int i = 1; i <= n; i++) cin >> w[i]; int sum = 0; for (int i = 1; i <= n; i++) sum += w[i]; if (sum % 2) { cout << "impossible" << endl; return 0; } vector dp(1e4 + 10, false); dp[0] = true; for (int i = 1; i <= n; i++) { for (int j = sum; j >= w[i]; j--) { if (dp[j - w[i]]) dp[j] = true; } } if (dp[sum / 2]) { cout << "possible" << endl; return 0; } cout << "impossible" << endl; }