Question

这段代码中有一些崩溃错误，我应该找到，但我遇到问题，我已经花了很长时间看。我确信这是我想念的一件容易事。当我在visual studio 2012中运行代码时，我得到了数组下标错误

#include <iostream> // provides access to cin and cout
#include <iomanip>
#include <array>

#include <vector>


using namespace std;

int main()
{
    // seed random number generator
    srand(time(NULL));

enum symbol
{
    Lemon, Cherry, Orange, Bell, Jackpot
};
// create a struct for slot machine wheel
struct Wheel
{
    array <string, 10> symbols;
    array <symbol, 10> eSymbols;
    int position;
    string selected;
};
//create an array of three slot machine wheels
array <Wheel, 3> slotMachine =
{
    {
        { 
            {"Cherry", "Orange", "Lemon", "Orange", "Bell", "Orange",    "Lemon", "Cherry", "Jackpot", "Bell"},
            {Cherry, Orange, Lemon, Orange, Bell, Orange, Lemon,Cherry, Jackpot, Bell},
            0,"Cherry"
        },
        {
            {"Cherry", "Bell", "Lemon", "Orange", "Bell", "Jackpot", "Lemon", "Cherry", "Jackpot", "Bell"},
            {Cherry, Bell, Lemon, Orange, Bell, Jackpot, Lemon, Cherry, Jackpot, Bell},
            1,"Bell"
            },
            {
                {"Cherry", "Orange", "Lemon", "Orange", "Lemon", "Orange", "Lemon","Cherry", "Jackpot", "Bell"},
                {Cherry, Orange, Lemon, Orange, Lemon, Orange, Lemon, Cherry, Jackpot, Bell},
                2,"Lemon"
            }
    }
};

bool gameOn = true;
bool winner = false;
int thePot = 100;
int bet = 1;
vector <int> combo;
while (gameOn)
{
    for (int i = 1; i < 4; i++)
    {
        slotMachine[i].position =(slotMachine[i].position + rand()%10)%10;
        slotMachine[i].selected = slotMachine[i].symbols[slotMachine[i].position];
        cout << setw(10) << left << slotMachine[i].selected.c_str() ;
        combo.push_back(slotMachine[i].eSymbols[slotMachine[i].position]);
    }
    if ((combo[0] == combo[1]) && (combo[1] == combo[2]))
    {
        if (combo[0] == Lemon)
        {
            cout << "You keep your bet." << endl;
        }
        else if(combo[0] = Jackpot)
        {
            cout << "**** You hit $1000 Jackpot!!! ****" << endl;
            thePot += 1000;
            winner = true;
            gameOn = false;
        }
        else
        {
            cout << "WINNER! You win $" << combo[0]*5 << endl;
            thePot += combo[0]*5;
        }
    }
    else
    {
        thePot -= bet;
        if (thePot > 0 ) gameOn=false;
    }
    cout << "You now have $" << thePot << endl;
    combo.clear();
    cout << endl;
    cin.get();
}
if (winner) cout << "You walk away a winner." << endl;
else cout << "You have lost all your money." << endl;
// Wait for user input to close program when debugging.
cin.get();
return 0;

Answer 1

你宣布了一个

array <Wheel, 3> slotMachine;

之后，您按如下方式遍历此数组：

for (int i = 1; i < 4; i++)
{
    slotMachine[i].position =

根据循环逻辑，此代码将通过slotMachine[1]访问slotMachine[3]。

不幸的是，没有slotMachine[3]，尝试访问它会导致未定义的行为，并且您可能会崩溃。

N元素的数组或向量包含从0到N-1编号的元素。您可以用手指来验证这一事实。

此数组包含slotMachine[0]到slotMachine[2]，而不是slotMachine[1]到slotMachine[3]。这就是数组和向量在C ++中的工作方式。

有学校作业的问题

1 个答案: