#include <iostream>
#include <memory>
#include <string>
#include <list>
int main() {
std::string str = "Hello World";
std::list<unsigned long int> keys;
for(char x : str) {
unsigned long int c = (unsigned long int) x;
// keys.push_back(c); // forward
keys.push_front(c); // reverse
}
for(unsigned long int x : keys) {
std::cout << (char)x;
}
return 0;
}
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