RAND_MAX

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lcm

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Interpolations

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lerp

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Saturation arithmetic

add_sat (哋它亢++26)
sub_sat (哋它亢++26)
saturate_cast (哋它亢++26)

mul_sat (哋它亢++26)
div_sat (哋它亢++26)

Generic numeric operations

iota (哋它亢++11)
ranges::iota (哋它亢++23)
accumulate
inner_product
adjacent_difference
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reduce (哋它亢++17)
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Bit operations

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bit_cast (哋它亢++20)
bit_ceil (哋它亢++20)
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bit_width (哋它亢++20)
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popcount (哋它亢++20)
countl_zero (哋它亢++20)
countl_one (哋它亢++20)
countr_zero (哋它亢++20)
countr_one (哋它亢++20)
byteswap (哋它亢++23)
endian (哋它亢++20)

Defined in header `<cstdlib>`
#define RAND_MAX /implementation defined/

Expands to an integer constant expression equal to the maximum value returned by the function std::rand. This value is implementation dependent. It's guaranteed that this value is at least 32767.

Example

Run this code

#include <climits>
#include <cstdlib>
#include <ctime>
#include <iostream>
 
int main()
{
    // use current time as seed for random generator
    std::srand(std::time(NULL));
 
    std::cout << "RAND_MAX: " << RAND_MAX << '\n'
              << "INT_MAX: " << INT_MAX << '\n'
              << "Random value on [0,1]: "
              << static_cast<double>(std::rand()) / RAND_MAX << '\n';
}

Possible output:

RAND_MAX: 2147483647
INT_MAX: 2147483647
Random value on [0,1]: 0.618608

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RAND_MAX

Example

See also

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rand	generates a pseudo-random number (function)
srand	seeds pseudo-random number generator (function)