Elevators

Whenever a new building is built, it must comply with all the relevant building regulations. In particular, there are rules governing the number of elevators a building must have depending on its number of floors and zoning district.

If a building has only one floor, it doesn’t need any elevators; otherwise, it needs more elevators the more floors it has, and the exact number depends on its zoning district. The following tables describe the number of elevators necessary for a building in each of the residential, commercial, and industrial zoning districts.

Residential |
Commercial |
Industrial |
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Floors |
Elevators |
Floors |
Elevators |
Floors |
Elevators |

$1$ |
$0$ |
$1$ |
$0$ |
$1$ |
$0$ |

$2-5$ |
$1$ |
$2-7$ |
$1$ |
$2-4$ |
$1$ |

$6-10$ |
$2$ |
$8-14$ |
$2$ |
$5-8$ |
$2$ |

$11-15$ |
$3$ |
$15-20$ |
$3$ |
$9-12$ |
$3$ |

$16-20$ |
$4$ |
$13-16$ |
$4$ |
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$17-20$ |
$5$ |

You are given the zoning district of a new building and how many floors it has. How many elevators does it need?

The only line of input contains a string representing the zoning district of the building (“residential”, “commercial”, or “industrial”), followed by a space and an integer $N$ ($1 \leq N \leq 20$), the number of floors the building has.

Output a single integer: the number of elevators the building must have.

Sample Input 1 | Sample Output 1 |
---|---|

residential 6 |
2 |

Sample Input 2 | Sample Output 2 |
---|---|

industrial 20 |
5 |