Question

我正在为我的计算机科学课编写游戏连接四个，一切都很好然后我不知道发生了什么但是每当我试图运行它时我都会遇到Sementation故障。这是我的代码。

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cctype>

using namespace std;

struct game{
    char **board;
    char p1;
    char p2;
};

void print_board(game p, int r, int c);
bool play(game p, bool gamewon, int r, int c, int pieces);
bool check(int a, int b, game p, int r, int c, int pieces);
int drop(int b, char player, game p, int c);


int main(int argc, char *argv[]){
    game p;
    int r, c, pieces;
    bool gamewon = false;
    /*if(argc == 7) {
       for(int i = 1; i < argc; i += 2) {
          if(argv[i][0]=='-' && argv[i][1]=='r')
             r = atoi(argv[i+1]);
          else if(!strcmp(argv[i],"-c"))
             c = atoi(argv[i+1]);
          else if(!strcmp(argv[i],"-p")){
             pieces = atoi(argv[i+1]);
             while (pieces < 1){
                cout << "You cannot have 0 pieces to connect." << endl;
                cout << "Please enter a positive, non-zero integer"
                << " for the number of pieces to connect: ";
                cin >> pieces;
                }
          }
          else 
             cout << "Error." << endl;      
       }
   }*/
    r = 6;
    c = 7;
    pieces = 4; 
    p.board = new char*[r];
    for(int i=0; i < r;i++)
        p.board[i] = new char[c]; 
    for(int a =0; a < r; a++){      
        for(int b = 0; b < c; b++)  
            p.board[a][b] = ' ';        
    }                               
    print_board(p, r, c);
        gamewon = play(p, gamewon, r, c, pieces);
    return 0;
}



bool play(game p, bool gamewon, int r, int c, int pieces){
    int col, hold = 0, charsPlaced = 0;
    char player = 'y';
    while(!gamewon){
        if(hold != -1){
            if(player =='y'){
                cout<<"Player 1, what column do you want to put your piece? ";
                player = 'r';
            }
            else{
                cout<<"Player 2, what column do you want to put your piece? ";
                player = 'y';
            }
        }
        while(true){
            if(charsPlaced == r*c) break;
            cin>>col;
            col--;
            if(col <=r && col>= 0) break;
            else cout<< "\nPlease enter a value between 1 and " << c << ": ";
            if (cin.fail()){                    
                cin.clear();        
                char d;         
                cin>>d;     
            }                   

        }
        if(charsPlaced == r*c) break;
        hold = drop(col,player, p, c);
        if(hold == -1)  cout<<"Column is full!\nPlease enter another number between 1 and " << c << ": ";
        else{
            gamewon = check(hold, col, p, r, c, pieces);
            charsPlaced ++;
            print_board(p, r, c);
        }
    }
    if(charsPlaced == r*c){
        cout<<"No winner! Game is a draw\n";
        return true;
    }
    if(player == 'y')
        cout<<"Player 2 is the winner!\n";
    else cout<<"Player 1 is the winner!\n";
    return true;

}    

void print_board(game p, int r, int c){
    cout << endl;
    for(int a = 0; a < r; a++){
        for(int b = 0; b < c; b++) 
           cout << "|" << p.board[a][b];
           cout << "|";
           cout << endl;
           for(int i = 0; i < c; i++)
              cout << "--";
              cout << endl;
    }
}

bool check(int a, int b, game p, int r, int c, int pieces){
    int vertical = 1, horizontal = 1, diagonalone = 1, diagonaltwo = 1, i , j;
    cout << i << " " << b << " " << a << endl;
    char player = p.board[a][b];
    cout << player << endl;
    for(i = a + 1; p.board[i][b] == player && i < r; i++, vertical++);
    for(i = a - 1; p.board[i][b] == player && i >= 0; i--, vertical++);
    if(vertical >= pieces)
        return true;
    for(j = b - 1; p.board[a][j] == player && j >= 0; j--, horizontal++);
    for(j = b + 1; p.board[a][j] == player && j < c; j++, horizontal++);
    if(horizontal >= pieces) 
        return true;
    for(i = a - 1, j = b - 1; p.board[i][j] == player && i >= 0 && j >= 0; diagonalone++, i--, j--);
    for(i = a + 1, j = b + 1; p.board[i][j] == player && i <= r && j <= c;diagonalone++, i++, j++);
    if(diagonalone >= pieces) 
        return true;
    for(i = a - 1, j = b + 1; p.board[i][j] == player && i >= 0 && j <= c; diagonaltwo++, i--, j++);
    for(i = a + 1, j = b - 1; p.board[i][j] == player && i <= r && j >= 0; diagonaltwo++, i++, j--);
    if(diagonaltwo >= pieces) 
        return true;
    return false;
}

int drop(int b, char player, game p, int c){
    if(b >= 0 && b <= c){
        if(p.board[0][b] == ' '){
            int i;
            for(i = 0; p.board[i][b] == ' '; i++)
                if(i == 5){
                    p.board[i][b] = player;
                    return i;
            }
            i--;
            p.board[i][b] = player;
            return i;

        }
        else{
            return -1;
        }

    }
    else{
        return -1;
    }

}

Answer 1

您正在使用

 char **board;

在你的游戏结构中。

但是这个2D数组永远不会被分配，但是你正在使用它。你错过了这样的东西：

在C：

board = malloc(10 * sizeof(char *));
for (int i = 0; i < 10; i++)
{
   board[i] = malloc(10 * sizeof(char));
}

在C ++中：

 board = new char*[10]
    for (int i = 0; i < 10; i++)
    {
       board[i] = new char[10];
    }

Answer 2

首先，如果你在Linux环境中，valgrind非常有助于找到你的分段错误。要使用它，如果您的程序被称为hello，只需将其作为valgrind hello运行。

调试这些的另一种方法是在代码中放置cout或printf语句，并观察最后的输出是什么。您可能正在索引超出数组的末尾。请记住，如果声明int x [5]，则有效索引值为0到4。

您可能需要将for循环更改为＆lt; vs.＆lt; =所以你没有读过电路板的最后一部分（请记住，数组在c ++中被编入索引）。

连接四个C ++

2 个答案: