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How to calculate the range of integer data types in ANSI C

What is the mathematical formula to calculate the range of signed, unsigned, short and long data types in ANSI C?

Solution

  • unsigned types have a range from 0 to 2^(effective number of bits used by the type) - 1

    signed types have a implementation defined minimum:

    2's complement -(2^(effective number of bits used by the type - 1))
    all others -(2^(effective number of bits used by the type - 1) - 1)

    the maximum for signed types is 2^(effective number of bits used by the type - 1) - 1

    ^ is the power function, not the xor.