Untitled

#include <iostream>

int main() {
	int total = 0;
	float avg = 0;
	int count = 0;
	int input = 0;

	while (true) {
		std::cin >> input;
		switch(input) {
		case 1:
			std::cin >> input;
			total += input;
			count++;
			avg = (float)total / count;
			break;
		case 2:
			std::cout << avg << std::endl;
			break;
		case 3:
			return 0;
		}
	}
}