Why we write "sizeof"

Answer 1

In C when you want to allocate memory you need to know the bitsize of a certain type that could be 4 bit for example
If you want to allocate memory for an array of 4 elements with a data type that needs 4 bit each you need to have 16 bits in the memory. Because sometimes you cant know how many bits a data type needs you use the function sizeof()

Answer 2

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