Float vs Double в Swift
/* Float can only hold seven digits of decimal numbers
while Double can hold twice the number. */
// i.e:
let valueOfPi: Float = 3.142857143
print(valueOfPi) // 3.142857
let valueOfRandomDecimal: Double = 7.1428571434322432345331
print(valueOfRandomNumber) // 7.142857143432243
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