Morse Code for LED in Linux

morse_led.cpp

#include <iostream>
#include <chrono>
#include <thread>
#include <vector>
#include <cstdio>

constexpr std::chrono::milliseconds operator""_tick(unsigned long long int tick) {
  return std::chrono::milliseconds(tick * 200);
}

int main () {
  using namespace std::chrono_literals;
  const std::vector<std::vector<int>> codes = {
    // A -- Z
    {0, 1},       {1, 0, 0, 0}, {1, 0, 1, 0}, {1, 0, 0},    {0},
    {0, 0, 1, 0}, {1, 1, 0},    {0, 0, 0, 0}, {0, 0},       {0, 1, 1, 1},
    {1, 0, 1},    {0, 1, 0, 0}, {1, 1},       {1, 0},       {1, 1, 1},
    {0, 1, 1, 0}, {1, 1, 0, 1}, {0, 1, 0},    {0, 0, 0},    {1},
    {0, 0, 1},    {0, 0, 0, 1}, {0, 1, 1},    {1, 0, 0, 1}, {1, 0, 1, 1},
    {1, 1, 0, 0}, 

    // 0 -- 9
    {0, 1, 1, 1, 1}, {0, 0, 1, 1, 1}, {0, 0, 0, 1, 1}, {0, 0, 0, 0, 1},
    {0, 0, 0, 0, 0}, {1, 0, 0, 0, 0}, {1, 1, 0, 0, 0}, {1, 1, 1, 0, 0}, 
    {1, 1, 1, 1, 0}, {1, 1, 1, 1, 1}, 
  };

  int c;
  while((c = std::getchar()) != EOF) {
    c = std::tolower(c);
    int index = -1;
    if ('a' <= c && c <= 'z') {
      index = c - 'a';
    } else if ('0' <= c && c <= '9') {
      index = c - '0' + 26;
    } else if (' ' == c) {
      std::this_thread::sleep_for(7_tick);
    }
    if (index == -1) continue;

    std::this_thread::sleep_for(3_tick);
    for (const auto key : codes[index]) {
      std::cout << '1';
      std::cout.flush();
      if (key) {
        std::this_thread::sleep_for(3_tick);
      } else {
        std::this_thread::sleep_for(1_tick);
      }
      std::cout << '0';
      std::cout.flush();
      std::this_thread::sleep_for(1_tick);
    }
  }
}