#include <iostream>
#include <string>
int main() {
std::string string;
std::getline(std::cin, string);
for (std::size_t i = 0; i != string.length(); ) {
if ((string[i] == 'a') || (string[i] == 'b')) {
string.erase(i, 1);
} else {
++i;
}
}
std::cout << string << std::endl;
}
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