#include #include // for STD(IN|OUT)_FILENO size_t my_atoi(const char* str){ size_t n = 0; char* s = (char*)str; while (*s != 0){ n *= 10; n += *s - '0'; ++s; } return n; } int main(const int argc, const char** argv){ char bits[65]; bits[64] = '\n'; for (auto j = 1; j < argc; ++j){ size_t n = my_atoi(argv[j]); for (char i = 0; i < 64; ++i){ bits[i] = '0' + (n & 1); n /= 2; } if (write(STDOUT_FILENO, bits, 65) != 65) return 1; } return 0; }