无脑使用标准库

#include <iostream>
#include <string>
#include <set>

int main(int argc, char const *argv[])
{
    std::string S,T;
    while (std::cin >> S >> T)
    {
        std::set<char> tst;
        bool rest = true;
        for (char c : T)
        {
            tst.insert(c);
        }

        for (char c : S)
        {
            if (!tst.count(c))
            {
                rest = false;
                break;
            }
        }
        std::cout << std::boolalpha << rest << std::endl;
    }

    return 0;
}