#include <iostream>
#include <string>
 
bool pangram(std::string s)
{
    int letters = 0;
    for (std::string::iterator it = s.begin(); it != s.end(); ++it)
    {
        int ltr = (*it | 32) - 97;
        if ((unsigned)ltr < 26) letters |= (1 << ltr);
    }
    //std::cout << std::hex << letters << std::endl;
    return letters == 0b11111111111111111111111111; // all 26 (0x3ffffff)
}
 
int main()
{
    std::string s;
    std::cout << "enter a sentence, to find out whether it is a pangram (all letters):";
    std::getline(std::cin, s);
    std::cout << (pangram(s) ? "yup" : "nope") << std::endl;
    return 0;
}
 

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