c++ - 骰子计数器无法正常工作(初学者)

Question

这是为了模拟 throw 2 个 6 面骰子而编写的。但是当我 throw 10 次时，它会随机 throw 任意数量的 throw (4、5、6 等)。我错过了什么吗？

#include <iostream>
#include <cmath>
#include <cstdlib>
#include <ctime>

using namespace std;

int throwDice()                // returns random number ranged 2-12
{
    int x = (rand() % 11) + 2;
    return x;
}


int main()
{
    srand (time(NULL));
    int y;
    cout << "Roll dice how many times?" << endl;
    cin >> y;

    int a2 = 0;
    int a3 = 0;
    int a4 = 0;
    int a5 = 0;
    int a6 = 0;
    int a7 = 0;
    int a8 = 0;
    int a9 = 0;
    int a10 = 0;
    int a11 = 0;
    int a12 = 0;

    for (int i = 0; i < y; i++)
    {
        throwDice();

    if (throwDice() == 2)
        a2++;
    else if (throwDice() == 3)
        a3++;
    else if (throwDice() == 4)
        a4++;
    else if (throwDice() == 5)
        a5++;
    else if (throwDice() == 6)
        a6++;
    else if (throwDice() == 7)
        a7++;
    else if (throwDice() == 8)
        a8++;
    else if (throwDice() == 9)
        a9++;
    else if (throwDice() == 10)
        a10++;
    else if (throwDice() == 11)
        a11++;
    else if (throwDice() == 12)
        a12++;
    }
    cout << "2 = " << a2 << endl;
    cout << "3 = " << a3 << endl;
    cout << "4 = " << a4 << endl;
    cout << "5 = " << a5 << endl;
    cout << "6 = " << a6 << endl;
    cout << "7 = " << a7 << endl;
    cout << "8 = " << a8 << endl;
    cout << "9 = " << a9 << endl;
    cout << "10 = " << a10 << endl;
    cout << "11 = " << a11 << endl;
    cout << "12 = " << a12 << endl;

    system("pause");
}

Answer 1

• 您调用一次 throwDice() 以生成抛出(正确)，然后在您的 if 语句中的每个评估条件中再次调用(不正确)。将抛出的结果保存在一个变量中，并在您的检查中使用该变量。

• 您的 throwDice 函数不模拟掷出两个 6 面骰子，但它模拟一个 11 面骰子(上面印有数字 2-11)它)被抛出。这很重要。 (虽然这不是编程问题，而是数学问题。一旦理解了它背后的数学原理，就很容易更正您的函数。)