10344.cpp

#include <algorithm>
#include <cstdio>
using namespace std;

int func(int tot, int val, int I) {
	switch (I) {
		case 0: return (tot + val);
		case 1: return (tot - val);
		case 2: return (tot * val);
	}
	return 0;
}

int main() {
	while (true) {
		int num[5];
		for (int i = 0; i < 5; i++)
			scanf("%d", &num[i]);
		if (count(num, num + 5, 0) == 5)
			break;
			
		bool flag = false;
		sort(num, num + 5);
		do {
			for (int a = 0; a < 3; a++)
				for (int b = 0; b < 3; b++)
					for (int c = 0; c < 3; c++)
						for (int d = 0; d < 3; d++) {
							int tot = num[0];
							tot = func(tot, num[1], a);
							tot = func(tot, num[2], b);
							tot = func(tot, num[3], c);
							tot = func(tot, num[4], d);
							if (tot == 23) {
								flag = true;
								break;
							}
						}
		} while (next_permutation(num, num + 5));
		
		if (flag)
			printf("Possible\n");
		else
			printf("Impossible\n");
	}
	return 0;
}