C++繪製卡片故障排除

Question

我被這個程序卡住了，似乎無法弄清楚它爲什麼會崩潰。它符合要求，但在運行時收集用戶輸入時會停止響應，迫使用戶關閉。

它所要做的就是詢問用戶他們想繪製多少張牌。一旦進入該程序，應該隨機選擇該手的數量，然後關閉。提前致謝！！

代碼：

#include <iostream> 
#include <iomanip> 
#include <ctime> 
#include <cstdlib> 
using namespace std; 

struct Card //defines a custom "structured" variable type 
{ 
    int kind; 
    char kindDisplay; 
    string suit; 
}; 

bool havePair (Card hand[]) 
{ 
    int count[13]; 
    int i,k; 
    bool pair; 

    for (i=0; i <=12; i++) 
    count[i] = 0; 

    for (i=1; i<= 5; i++) 
    count[hand[i].kind]++; 
    pair = false; 

    for (i=0; i <= 12;i++) 
    if (count[i] > 1) 
     pair = true; 
    return pair; 

} 

int main() 
{ 
    int numHands; 
    int pairCount =0; 
    bool hasBeenDrawn[52]; // has given card been drawn already? 
    int  suitDrawn;   // 0=clubs,1=diamonds,2=spades,3=hearts 
    int  kindDrawn;    // index of kind from 0 to 12, 
           // representing 2,3,...9,10,J,Q,K,A 
    Card hand[6]; 
    int  num;  // randomly generated card to pick (from 0 to 51). 
    int  cardCount; // counts how many cards have been drawn; 
    int  i,j; 
    unsigned int seed; // seed for random number generator 

    seed = time(0);  
    srand(seed); 

    cout << "Enter # of hands to draw: "; 
    cin >> numHands; 
    cout << endl; 
    for (j=1; j<= numHands; j++) 
    { 

     for (i=0; i < 52; i ++) 
      hasBeenDrawn[i] = false; 

     for (cardCount=1; cardCount <=5; cardCount++) // draw 5 cards 
     { 
     do 
     { 
      num = rand()%52; // get random number between 0 & 51 inclusive 
     } while (hasBeenDrawn[num] == true); 

     hasBeenDrawn[num] = true; 

     suitDrawn = num/13; // quotient will be 0, 1, 2, or 3 

     switch (suitDrawn) 
     { 
      case 0: hand[cardCount].suit = " clubs "; 
       break; 
      case 1: hand[cardCount].suit = " diamonds"; 
       break; 
      case 2: hand[cardCount].suit = " spades "; 
       break; 
      case 3: hand[cardCount].suit = " hearts "; 
       break; 
     } 
     kindDrawn = num % 13; 
     hand[cardCount].kind = kindDrawn; 

     if  (kindDrawn == 12) hand[cardCount].kindDisplay = 'A'; 
     else if (kindDrawn == 11) hand[cardCount].kindDisplay = 'K'; 
     else if (kindDrawn == 10) hand[cardCount].kindDisplay = 'Q'; 
     else if (kindDrawn == 9) hand[cardCount].kindDisplay = 'J'; 
     else if (kindDrawn == 8) hand[cardCount].kindDisplay = 'T'; // a "ten" 
     else 
           hand[cardCount].kindDisplay = (char)(kindDrawn + 50); 

     if (havePair(hand) == true) 
      pairCount++; 
     } 

     //Note: ASCII character codes for '0','1',...,'9' are 48 through 57 
     } // end for loop (cardCount = 1 to 5) draw 5 cards 
     cout << endl << endl; 
     cout << fixed << setprecision(2); 
     cout << "Experimental % of pairs: " << (double)numHands*100.0 << endl; 
     cout << "Theoretical % of pairs: " << (2598960-1317888)/(double)(2598960)*100.0 << endl; //approximate # of hands that don't have a pair 
     cout << endl; 
    return 0; 

} 

Answer 1

你hand陣列時，您呼叫的havePair()功能尚未初始化。

您應該在完成手陣列填充後，從循環外調用havePair()函數。

編輯：正如John3136所建議的，這是開始使用調試器的好時機。它將幫助你在將來解決這些錯誤。

更改havePair()功能：

int numOfPairs (Card hand[]) 
{ 
    int count[13]; 
    int i,k; 
    int pair; 

    for (i=0; i <=12; i++) 
    count[i] = 0; 

    for (i=1; i<= 5; i++) 
    count[hand[i].kind]++; 
    pair = 0; 

    for (i=0; i <= 12;i++) 
    if (count[i] > 1) 
     pair++; 
    return pair; 

} 

而且這一部分：

 if (havePair(hand) == true) 
     pairCount++; 
    } 

    //Note: ASCII character codes for '0','1',...,'9' are 48 through 57 
    } // end for loop (cardCount = 1 to 5) draw 5 cards 
    cout << endl << endl; 

到

 pairCount = numOfPairs(hand); 
    //Note: ASCII character codes for '0','1',...,'9' are 48 through 57 
    } // end for loop (cardCount = 1 to 5) draw 5 cards 

    cout << endl << endl;