#include <iostream>
#include <string>
#include <cmath>
#include <vector>
#include <algorithm>

using namespace std;

bool min_bigger_than(std::string& smin, std::string& snum, bool strictly_bigger, int beg = 0)
{
	if (smin.size() == snum.size() && !strictly_bigger)
	{
		for (int i = beg; i < smin.size(); i++)
		{
			if (snum[i] == '6' || snum[i] == '9')
			{
				if (strictly_bigger)
					snum[i] = '6';

				else
				{
					// smin[i] is > 6, snum[i] is 6
					if (smin[i] > snum[i])
					{
						snum[i] = '9';
						return min_bigger_than(smin, snum, smin[i] == snum[i], i + 1);
					}

					// Both are either 6 or 9
					else if (smin[i] == snum[i])
					{
						bool res = min_bigger_than(smin, snum, false, i + 1);
						if (snum[i] == '6')
						{
							if (!res)
								snum[i] = '9';

							return true;
						}

						return res;
					}

					// smin[i] is < 9, snum[i] is 9
					else
					{
						if (smin[i] < '6' || (smin[i] == '6' && min_bigger_than(smin, snum, false, i + 1)))
							snum[i] = '6';
						return true;
					}
				}
			}

			else
			{
				if (snum[i] > smin[i])
					strictly_bigger = true;

				if (!strictly_bigger && snum[i] < smin[i])
					return false;
			}
		}

		return true;
	}

	else if (smin.size() > snum.size())
		return false;

	else
	{
		for (int i = beg; i < snum.size(); i++)
			if (snum[i] == '9')
				snum[i] = '6';
		return true;
	}
}


int main()
{
	int n;
	scanf("%d", &n);

	std::vector<long long> vec(n + 1);
	vec[0] = 0;

	for (int i = 1; i <= n; i++)
		scanf("%lld", &vec[i]);

	for (int i = 1; i <= n; i++)
	{
		std::string str_prev = std::to_string(vec[i - 1]),
			str_cur = std::to_string(vec[i]);

		if (!min_bigger_than(str_prev, str_cur, false))
		{
			printf("impossible\n");
			return 0;
		}

		vec[i - 1] = std::stoll(str_prev);
		vec[i] = std::stoll(str_cur);
	}

	printf("possible\n");
	for (int i = 1; i <= n; i++)
		printf("%lld\n", vec[i]);
}