Variables and Data Types

Variables and the int, float, str, bool types; arithmetic and division quirks.

A variable is a name bound to a value. In Python you don't declare the type: the language infers it from the value. The core types: • int — integers. A nice Python bonus: they never overflow, you can compute with 100-digit numbers; • float — floating-point numbers, e.g. 3.14; • str — a string, text in quotes; • bool — True or False.
Python

Variables and the type function

Arithmetic: + - * , and division in Python has an important subtlety: • / — regular division, the result is always fractional: 7 / 2 equals 3.5; • // — integer division: 7 // 2 equals 3; • % — remainder: 7 % 2 equals 1; • ** — exponentiation: 2 ** 10 equals 1024. Contest problems usually need // and %: remember the difference between / and //, it is a classic mistake.
Python

Kinds of division and big numbers

Task: create variables with the values 15 and 4 and print their sum, difference, product, integer quotient and remainder — each on its own line. Then mark the lesson as completed.
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