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Qroia FAK(C)E
Qroia FAK(C)E

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Codewars Challenge Day 5: JS, Python + SQL and PHP

#javascript #python #sql #php

JavaScript & Python

Details

Name Kata: Sum of Digits / Digital Root
6kuy
Description: Given n, take the sum of the digits of n. If that value has more than one digit, continue reducing in this way until a single-digit number is produced. The input will be a non-negative integer.
Example:

 16 --> 1 + 6 = 7 942 --> 9 + 4 + 2 = 15 --> 1 + 5 = 6 132189 --> 1 + 3 + 2 + 1 + 8 + 9 = 24 --> 2 + 4 = 6 493193 --> 4 + 9 + 3 + 1 + 9 + 3 = 29 --> 2 + 9 = 11 --> 1 + 1 = 2
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My Solutions

Python 

def digital_root(n: int) -> int: n_str = str(n) while len(n_str) > 1: r = 0 for i in range(len(n_str)): r = r + int(n_str[i]) n_str = str(r) return n if (n >= 0 and len(str(n)) == 1) else r
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JavaScript(TypeScript4) 

export const digitalRoot = (n:number):number => { return String(n).length == 1 ? n : digitalRoot( String(n).split("").map((n) => Number(n)).reduce( (previousValue, currentValue) => previousValue + currentValue, 0) ) };
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PHP

Details

Name Kata: You're a square!
7kuy
Description: You like building blocks. You especially like building blocks that are squares. And what you even like more, is to arrange them into a square of square building blocks!

However, sometimes, you can't arrange them into a square. Instead, you end up with an ordinary rectangle! Those blasted things! If you just had a way to know, whether you're currently working in vain… Wait! That's it! You just have to check if your number of building blocks is a perfect square.
Task

Given an integral number, determine if it's a square number:

In mathematics, a square number or perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with itself.
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The tests will always use some integral number, so don't worry about that in dynamic typed languages.
Example:

-1 => false 0 => true 3 => false 4 => true 25 => true 26 => false
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My Solutions 

function isSquare(int $n): bool { return sqrt($n) == (int)sqrt($n) ? true : false; }
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SQL

Details

Name Kata: SQL Basics: Truncating
7kuy
Description: Given the following table 'decimals':
decimals table schema

id number1 number2
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Return a table with a single column towardzero where the values are the result of number1 + number2 truncated towards zero.

My Solutions 

SELECT TRUNC(number1 + number2) AS towardzero FROM decimals
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