#include<iostream>
#include<string>

int main() {
	std::string code;
	std::cin >> code;

	for (int i = 0; i < code.length(); i++) {
		code[i] -= (i + 1) % 26;
		if (code[i] < 'A')code[i] += 26;
	}
	std::cout << code << std::endl;
	return 0;
}