A geração de números aleatórios é um requisito comum em muitas aplicações de programação, e C++ fornece diversas maneiras de gerar números aleatórios dentro de um determinado intervalo. Neste artigo, exploraremos diferentes métodos para gerar números aleatórios entre 1 e 10 em C++.
Método 1:
Usando a função Rand():
Um dos métodos mais simples para gerar um número aleatório entre 1 e 10 em C++ é o Rand() função. Esta função é definida no arquivo de cabeçalho e gera um número inteiro aleatório dentro de um intervalo de 0 para RAND_MAX . O valor de RAND_MAX depende da implementação e pode variar de compilador para compilador.
Exemplo:
Vamos dar um exemplo para gerar um número aleatório entre 1 e 10 usando a função Rand(), podemos usar o seguinte código:
#include #include #include using namespace std; int main() { srand(time(0)); cout<< 'Random number between 1 and 10 is: '<<endl; for(int i="0;i<10;i++)" cout << (rand() % 10) + 1<<' '; return 0; } < pre> <p> <strong>Output</strong> </p> <pre> Random number between 1 and 10 is: 4 5 7 10 7 5 1 7 10 2 </pre> <p>In this code, we have included the <strong> <em></em> </strong> and <strong> <em></em> </strong> header files. The <strong> <em>srand()</em> </strong> function is used to initialize the random number generator with the current time as the seed. It ensures that every time the program is run, a new sequence of random numbers is generated.</p> <p>The <strong> <em>rand()</em> </strong> function is used to generate a random integer between 0 and <strong> <em>RAND_MAX</em> </strong> . To limit the range between 1 and 10, we take the remainder of this number when divided by 10 and add 1 to it.</p> <h3>Method 2:</h3> <p> <strong>Using C++11 random library</strong> </p> <p>The <strong> <em>C++11</em> </strong> standard introduced a new library called <strong> <em></em> </strong> that provides a better way to generate random numbers. This library provides several random number generation engines and distributions that can generate random numbers with a uniform distribution.</p> <p> <strong>Example:</strong> </p> <p>Let's take an example to generate a random number between 1 and 10 using the <strong> <em></em> </strong> library, we can use the following code:</p> <pre> #include #include using namespace std; int main() { random_device rand; mt19937 gen(rand()); uniform_int_distributiondis(1, 10); int random_number = dis(gen); cout<< 'Random number between 1 and 10 is: ' <<random_number<<endl; return 0; } < pre> <p>In this code, we have included the <strong> <em></em> </strong> header file. The <strong> <em>random_device</em> </strong> class is used to obtain a seed value for the random number generator. The <strong> <em>mt19937</em> </strong> class is a random number generation engine that produces random numbers with a uniform distribution. The <strong> <em>uniform_int_distribution</em> </strong> class is used to generate random integers within a given range.</p> <p>By default, the <strong> <em>mt19937</em> </strong> engine uses a seed value of <strong> <em>5489</em> </strong> , which can be changed using the <strong> <em>seed()</em> </strong> method. However, it is recommended to use a <strong> <em>random_device</em> </strong> to obtain a seed value for better randomness.</p> <p>The <strong> <em>uniform_int_distribution</em> </strong> class generates random integers with a uniform distribution within a given range. In this code, we have specified the range as <strong> <em>1</em> </strong> to <strong> <em>10</em> </strong> using the constructor.</p> <p>This method provides better randomness and a uniform distribution of generated numbers compared to the <strong> <em>rand()</em> </strong> function. However, it is slower and more complex to implement.</p> <h3>Method 3:</h3> <p> <strong>Using modulo operator with time():</strong> </p> <p>Another method to generate a random number between 1 and 10 is the <strong> <em>modulo operator</em> </strong> with the current time as a seed value. This method is similar to the first method using <strong> <em>rand()</em> </strong> function, but it uses a more random seed value and provides better randomness.</p> <p> <strong>Example:</strong> </p> <p>Let's take an example to generate a random number between 1 and 10 using the modulo operator with <strong> <em>time()</em> </strong> , we can use the following code:</p> <pre> #include #include using namespace std; int main() { srand(time(0)); cout<< 'Random number between 1 and 10 is: ' <<endl; for(int i="0;i<10;i++)" cout << (rand() % 10) + 1<<' '; return 0; } < pre> <p> <strong>Output</strong> </p> <pre> Random number between 1 and 10 is: 6 6 3 6 10 10 1 7 6 4 </pre> <p>In this code, we have used the <strong> <em>time()</em> </strong> function to obtain the current time as a seed value for the <strong> <em>srand()</em> </strong> function. The <strong> <em>srand()</em> </strong> function is used to initialize the random number generator. The <strong> <em>rand()</em> </strong> function generates a random integer between 0 and <strong> <em>RAND_MAX</em> </strong> , which is then limited to a range between 1 and 10 using the <strong> <em>modulo operator</em> </strong> and adding 1 to it.</p> <h2>Conclusion:</h2> <p>In conclusion, there are several methods to generate random numbers between 1 and 10 in C++. The choice of method depends on the requirements of the application, such as <strong> <em>speed, randomness</em> </strong> , and <strong> <em>uniformity</em> </strong> of generated numbers. While the <strong> <em>rand()</em> </strong> function is the simplest and easiest to implement, it may not provide good randomness and uniformity. The <strong> <em></em> </strong> library provides a better way to generate random numbers with a uniform distribution, but it is slower and more complex to implement. The <strong> <em>XORShift</em> </strong> algorithm provides good <strong> <em>randomness</em> </strong> and <strong> <em>uniformity</em> </strong> , but it is more complex to implement and may not be as fast as the <strong> <em>rand()</em> </strong> function.</p> <hr></endl;></pre></random_number<<endl;></pre></endl;> Neste código, incluímos o e arquivos de cabeçalho. O srand() A função é usada para inicializar o gerador de números aleatórios com a hora atual como semente. Garante que toda vez que o programa for executado, uma nova sequência de números aleatórios seja gerada.
O Rand() função é usada para gerar um número inteiro aleatório entre 0 e RAND_MAX . Para limitar o intervalo entre 1 e 10, pegamos o resto desse número quando dividido por 10 e adicionamos 1 a ele.
Método 2:
Usando a biblioteca aleatória C++ 11
O C++11 padrão introduziu uma nova biblioteca chamada que fornece uma maneira melhor de gerar números aleatórios. Esta biblioteca fornece vários mecanismos e distribuições de geração de números aleatórios que podem gerar números aleatórios com uma distribuição uniforme.
Exemplo:
Vamos dar um exemplo para gerar um número aleatório entre 1 e 10 usando o biblioteca, podemos usar o seguinte código:
#include #include using namespace std; int main() { random_device rand; mt19937 gen(rand()); uniform_int_distributiondis(1, 10); int random_number = dis(gen); cout<< 'Random number between 1 and 10 is: ' <<random_number<<endl; return 0; } < pre> <p>In this code, we have included the <strong> <em></em> </strong> header file. The <strong> <em>random_device</em> </strong> class is used to obtain a seed value for the random number generator. The <strong> <em>mt19937</em> </strong> class is a random number generation engine that produces random numbers with a uniform distribution. The <strong> <em>uniform_int_distribution</em> </strong> class is used to generate random integers within a given range.</p> <p>By default, the <strong> <em>mt19937</em> </strong> engine uses a seed value of <strong> <em>5489</em> </strong> , which can be changed using the <strong> <em>seed()</em> </strong> method. However, it is recommended to use a <strong> <em>random_device</em> </strong> to obtain a seed value for better randomness.</p> <p>The <strong> <em>uniform_int_distribution</em> </strong> class generates random integers with a uniform distribution within a given range. In this code, we have specified the range as <strong> <em>1</em> </strong> to <strong> <em>10</em> </strong> using the constructor.</p> <p>This method provides better randomness and a uniform distribution of generated numbers compared to the <strong> <em>rand()</em> </strong> function. However, it is slower and more complex to implement.</p> <h3>Method 3:</h3> <p> <strong>Using modulo operator with time():</strong> </p> <p>Another method to generate a random number between 1 and 10 is the <strong> <em>modulo operator</em> </strong> with the current time as a seed value. This method is similar to the first method using <strong> <em>rand()</em> </strong> function, but it uses a more random seed value and provides better randomness.</p> <p> <strong>Example:</strong> </p> <p>Let's take an example to generate a random number between 1 and 10 using the modulo operator with <strong> <em>time()</em> </strong> , we can use the following code:</p> <pre> #include #include using namespace std; int main() { srand(time(0)); cout<< 'Random number between 1 and 10 is: ' <<endl; for(int i="0;i<10;i++)" cout << (rand() % 10) + 1<<\' \'; return 0; } < pre> <p> <strong>Output</strong> </p> <pre> Random number between 1 and 10 is: 6 6 3 6 10 10 1 7 6 4 </pre> <p>In this code, we have used the <strong> <em>time()</em> </strong> function to obtain the current time as a seed value for the <strong> <em>srand()</em> </strong> function. The <strong> <em>srand()</em> </strong> function is used to initialize the random number generator. The <strong> <em>rand()</em> </strong> function generates a random integer between 0 and <strong> <em>RAND_MAX</em> </strong> , which is then limited to a range between 1 and 10 using the <strong> <em>modulo operator</em> </strong> and adding 1 to it.</p> <h2>Conclusion:</h2> <p>In conclusion, there are several methods to generate random numbers between 1 and 10 in C++. The choice of method depends on the requirements of the application, such as <strong> <em>speed, randomness</em> </strong> , and <strong> <em>uniformity</em> </strong> of generated numbers. While the <strong> <em>rand()</em> </strong> function is the simplest and easiest to implement, it may not provide good randomness and uniformity. The <strong> <em></em> </strong> library provides a better way to generate random numbers with a uniform distribution, but it is slower and more complex to implement. The <strong> <em>XORShift</em> </strong> algorithm provides good <strong> <em>randomness</em> </strong> and <strong> <em>uniformity</em> </strong> , but it is more complex to implement and may not be as fast as the <strong> <em>rand()</em> </strong> function.</p> <hr></endl;></pre></random_number<<endl;> Neste código, usamos o tempo() função para obter a hora atual como um valor inicial para o srand() função. O srand() função é usada para inicializar o gerador de números aleatórios. O Rand() função gera um número inteiro aleatório entre 0 e RAND_MAX , que é então limitado a um intervalo entre 1 e 10 usando o módulo operador e adicionando 1 a ele.
Conclusão:
Concluindo, existem vários métodos para gerar números aleatórios entre 1 e 10 em C++. A escolha do método depende dos requisitos da aplicação, como velocidade, aleatoriedade , e uniformidade de números gerados. Enquanto o Rand() é a mais simples e fácil de implementar, ela pode não fornecer boa aleatoriedade e uniformidade. O A biblioteca fornece uma maneira melhor de gerar números aleatórios com uma distribuição uniforme, mas é mais lenta e complexa de implementar. O XORShift algoritmo fornece boa aleatoriedade e uniformidade , mas é mais complexo de implementar e pode não ser tão rápido quanto o Rand() função.