JavaScript
const unluckyDays = year => { let unlucky = 0; for (x = 0; x < 12; x++) { unlucky += new Date(year, x, 13).getDay() === 5 ? 1 : 0; } return unlucky; }
Live demo on CodePen
Brilliant solution, very simple and effective. Although I think ? 1 : 0 is not necessary :p
? 1 : 0
Yes. It's not really necessary because true is turn into 1, and false to 0. I have a second version using that and a reducer in the demo.
true
false
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JavaScript
Live demo on CodePen
Brilliant solution, very simple and effective. Although I think
? 1 : 0is not necessary :pYes. It's not really necessary because
trueis turn into 1, andfalseto 0. I have a second version using that and a reducer in the demo.