c++ random number within range
To generate a random number within a specific range in C++, you can use the <random>
library. Here are the steps to do it:
- Include the
<random>
header file at the beginning of your program:
#include <random>
- Create an instance of the
std::random_device
class. This is used to generate a seed for the random number generator. The seed is typically based on some source of entropy from the operating system.
std::random_device rd;
- Create an instance of the
std::mt19937
class. This is a random number engine that generates random numbers based on a specific algorithm. In this case, we are using the Mersenne Twister algorithm.
std::mt19937 gen(rd());
- Define the range of the random numbers you want to generate. For example, if you want to generate a random number between 1 and 10, you can use the
std::uniform_int_distribution
class:
std::uniform_int_distribution<int> dis(1, 10);
- Generate a random number within the specified range using the
operator()
of the distribution object and the random number engine:
int random_num = dis(gen);
Now, random_num
will contain a random number between 1 and 10.
Here's the complete code:
#include <random>
int main() {
std::random_device rd;
std::mt19937 gen(rd());
std::uniform_int_distribution<int> dis(1, 10);
int random_num = dis(gen);
// Use the random number here
return 0;
}
Remember to include the <random>
header file and use the std::random_device
and std::mt19937
classes to generate a seed and create a random number engine respectively. Then, define the range using the std::uniform_int_distribution
class and generate the random number using the operator()
of the distribution object and the random number engine.