7. Miners

include <iostream>
#include <map>
#include <queue>

using namespace std;

int main()
{
	map<string, int> mines;
	queue<string> order;
	while (true)
	{
		string resource;
		cin >> resource;
		if (resource == "stop")
		{
			break;
		}

		int quantity;
		cin >> quantity;

		if (mines.find(resource) == mines.end())
		{
			order.push(resource);
		}

		mines[resource] += quantity;
	}

	while (!order.empty())
	{
		string element = order.front();
		cout << element << " -> " << mines[element] << endl;
		order.pop();
	}

	return 0;
}