std::experimental::randint

C++

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Technical Specifications

Technical specifications

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals 2 TS)

Extensions for parallelism (parallelism TS)

Extensions for parallelism 2 (parallelism TS v2)

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Library fundamentals v2

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experimental::randint

detection idiom

uniform container erasure

logical operator type traits

Defined in header <experimental/random>
template <class IntType> IntType randint(IntType a, IntType b);		(library fundamentals TS v2)

Generates a random integer in the closed interval [a, b].

Parameters

a, b

-

integer values specifying the range

Return value

A random integer i in the closed interval [a, b], produced using a thread-local instance of std::uniform_int_distribution<IntType> invoked with the per-thread random number engine.

Remarks

If IntType is not one of short, int, long, long long, unsigned short, unsigned int, unsigned long, or unsigned long long, the program is ill-formed.

The behavior is undefined if a > b.

Example

Run this code

#include <iostream>
#include <experimental/random>

int main()
{
    int random_number = std::experimental::randint(100, 999);
    std::cout << "random 3-digit number: " << random_number << '\n';
}

Possible output:

random 3-digit number: 273

See also

reseed

reseeds the per-thread random engine (function)