#include <algorithm>
#include <iostream>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
using namespace std;

template<typename Cmp, typename T>
void
heapsort(vector<T> &vec, Cmp cmp)
{
	make_heap(vec.begin(), vec.end(), cmp);
	for (size_t i = 0; i < vec.size(); i++) {
		pop_heap(vec.begin(), vec.begin() + vec.size() - i, cmp);
	}
}
template<typename T>
void
heapsort(vector<T> &vec)
{
	heapsort(vec, less<T>());
}

bool
string_rcmp(const string &a, const string &b)
{
	return lexicographical_compare(
	  a.rbegin(), a.rend(), b.rbegin(), b.rend());
}

int
main2()
{
	vector<string> v;

	string x;
	for (size_t i = 0; i < 10; i++) {
		cin >> x;
		v.push_back(x);
	}
	cout << "=================" << endl;
	heapsort(v, string_rcmp); // , [](int x, int y)->bool {return x > y; });
	for (auto &&i : v) {
		cout << i << endl;
	}
	return 0;
}

/////////////////////////////////////////////

void
print_p(const vector<int> &v)
{
	for (size_t i = 0; i < v.size(); i++) {
		cout << v[i] << "x^" << i << " ";
	}
	cout << endl;
}

int
main()
{
	stack<vector<int>> s;
	string str;
	while (cin >> str) {
		if (str == "p") {
			if (!s.empty()) {
				print_p(s.top());
				s.pop();
			}
		} else if (str == "+") {
			if (s.size() >= 2) {
				auto a = s.top();
				s.pop();
				auto b = s.top();
				s.pop();
				a.resize(max(a.size(), b.size()));
				for (size_t i = 0; i < b.size(); i++)
					a[i] += b[i];
				s.push(a);
			} else {
				cout << "?" << endl;
			}
		} else if (str == "*") {
			if (s.size() >= 2) {
				auto a = s.top();
				s.pop();
				auto b = s.top();
				s.pop();
				vector<int> c(a.size() + b.size());
				for (size_t i = 0; i < a.size(); ++i) {
					for (size_t j = 0; j < b.size(); ++j) {
						c[i + j] += a[i] * b[j];
					}
				}
				s.push(c);
			} else {
				cout << "?" << endl;
			}
		} else if (str == "d") {
			if (s.size()) {
				auto a = s.top();
				s.push(a);
			} else {
				cout << "?" << endl;
			}
		} else if (str == "x") {
			vector<int> a;
			a.push_back(0);
			a.push_back(1);
			s.push(a);
		} else if (!str.empty() &&
		           all_of(str.begin(), str.end(), isdigit)) {
			stringstream ss(str);
			int n;
			ss >> n;
			vector<int> a;
			a.push_back(n);
			s.push(a);
		} else {
			cout << '?' << endl;
		}
	}

	return 0;
}