C 程序中的 Char 变量行为

标签 c char typedef

我编写了一个数独求解器程序，其功能是检查在特定位置设置值是否合法:

typedef int cell;
typedef char value;
typedef value sudokuGrid[GRID_SIZE]; // GRID_SIZE is 81


int isLegal (sudokuGrid game, cell location,value candidateDigit);

我还编写了一个函数来测试 isLegal 函数，给它一个数独谜题，一旦计算出解决方案，检查所有设置值是否正确:

static void testIsLegal(){
   int i, solution;
   int mid_result, result;

   sudokuGrid testGrid = {
      '6','4','.','.','.','.','8','1','7',
      '1','7','.','8','6','.','2','.','4',
      '.','.','.','.','.','.','.','9','6',
      '.','8','.','.','9','6','.','.','.',
      '.','6','.','3','.','1','.','2','.',
      '.','.','.','2','5','.','.','6','.',
      '8','2','.','.','.','.','.','.','.',
      '3','.','7','.','1','8','.','4','2',
      '4','5','1','.','.','.','.','8','3'
   };


   printf("Testing isLegal() function ............\n");

   result = TRUE;


   solution = hasSolution(testGrid);
   showGame(testGrid);

   int f = isLegal(testGrid,78,'9');
   printf("isLegal(testGrid,78,9) = %d\n\n",f);


   i = 0;
   result = TRUE;
   value cellValue;
   if (solution){
      while ((result == TRUE) && (i < GRID_SIZE)){
         cellValue = testGrid[i];
         testGrid[i] = EMPTY_VALUE;
         printf("isLegal(testGrid,%d,%c) = %d\n",i,cellValue,isLegal(testGrid,i,cellValue));
         result = result && isLegal(testGrid,i,cellValue);
         testGrid[i] = cellValue;
         i++;
      }
    }
    if (result)
         printf("\t\t\t\t\t [OK]\n");
      else
         printf("\t\t\t\t\t[NOK]\n");
}

执行该函数的结果是错误的:

6 4 2   5 3 9   8 1 7
1 7 5   8 6 2   2 3 4
9 3 8   1 4 7   5 9 6

2 8 3   7 9 6   1 7 5
5 6 4   3 8 1   3 2 8
7 1 9   2 5 4   4 6 9

8 2 6   4 2 3   6 5 1
3 9 7   6 1 8   7 4 2
4 5 1   9 7 5   9 8 3

这里有很多错误，但我在最后一行提到了两个 9(位置 75 和 78)。对 isLegal(testGrid,78,'9') 执行手动检查，该检查返回 FALSE，但当我使用循环时 isLegal(testGrid,i,cellValue) 始终返回 TRUE:

isLegal(testGrid,78,9) = 0

isLegal(testGrid,0,6) = 1
isLegal(testGrid,1,4) = 1
isLegal(testGrid,2,2) = 1
isLegal(testGrid,3,5) = 1
.....
isLegal(testGrid,78,9) = 1
isLegal(testGrid,79,8) = 1
isLegal(testGrid,80,3) = 1

我的问题是，为什么当我在 ' ' 引号中使用 char 变量(代码中的 isLegal(testGrid,78,'9') )时，它会显示正确的结果，但当我使用 cellValue 变量时却不会？ 如何解决这个问题？

谢谢!

添加附加信息:

#define MIN_VALUE '1'
#define MAX_VALUE '9'
#define EMPTY_VALUE '.'
#define NUM_VALUES (MAX_VALUE - MIN_VALUE + 1)
#define GRID_SIZE (NUM_VALUES * NUM_VALUES)
#define MAX_CELL (GRID_SIZE - 1)

#define TRUE    1
#define FALSE   0

#define MINI_SQUARE_SIZE        3
#define SQUARE_SIZE             9

typedef int cell;
typedef char value;
typedef value sudokuGrid[GRID_SIZE];

isLegal 函数:

int isLegal (sudokuGrid game, cell location,value candidateDigit){
   assert (location >= 0);
   assert (location <= GRID_SIZE);

   assert (candidateDigit >= MIN_VALUE);
   assert (candidateDigit <= MAX_VALUE);

   return (isLegalLine(game,location,candidateDigit) &&
            isLegalColumn(game,location,candidateDigit) &&
            isLegalSquare(game,location,candidateDigit));
}




static int isLegalLine(sudokuGrid game, cell location,value candidateDigit){
   assert (location >= 0);
   assert (location <= GRID_SIZE);

   assert (candidateDigit >= MIN_VALUE);
   assert (candidateDigit <= MAX_VALUE);


   int result, mid_result;
   int i;
   int lineNumber = location / SQUARE_SIZE;

   result = TRUE;

   for (i = 0; i < GRID_SIZE; i++){
      if (( i / SQUARE_SIZE ) == lineNumber){
         if ( game[i] != candidateDigit ){
            mid_result = TRUE;
         }
         else{
            mid_result = FALSE;
         }
         result = result && mid_result;
      }
   }

   return result;
}

static int isLegalColumn(sudokuGrid game, cell location,value candidateDigit){
   assert (location >= 0);
   assert (location <= GRID_SIZE);

   assert (candidateDigit >= MIN_VALUE);
   assert (candidateDigit <= MAX_VALUE);


   int result, mid_result;
   int i;
   int columnNumber = location % SQUARE_SIZE;

   result = TRUE;

   for (i = 0; i < GRID_SIZE; i++){
      if (( i % SQUARE_SIZE ) == columnNumber){
         if ( game[i] != candidateDigit )
             mid_result = TRUE;
         else
             mid_result = FALSE;
         result = result && mid_result;
      }
   }
   return result;
}

static int isLegalSquare(sudokuGrid game, cell location,value candidateDigit){
   assert (location >= 0);
   assert (location <= GRID_SIZE);

   assert (candidateDigit >= MIN_VALUE);
   assert (candidateDigit <= MAX_VALUE);


   int result, mid_result;
   int i;

   int lineNumber = location / SQUARE_SIZE;
   int columnNumber = location % SQUARE_SIZE;
//   int squareNumber;

   if ( lineNumber < MINI_SQUARE_SIZE){
      lineNumber = 0;
      if (columnNumber < MINI_SQUARE_SIZE){
      //   squareNumber = 1;
         columnNumber = 0;
      }
      else if (columnNumber < 2*MINI_SQUARE_SIZE){
      //   squareNumber = 2;
         columnNumber = MINI_SQUARE_SIZE;
      }
      else{
      //   squareNumber = 3;
         columnNumber = 2*MINI_SQUARE_SIZE;
      }
   }

   else if (lineNumber < 2*MINI_SQUARE_SIZE){
      lineNumber = MINI_SQUARE_SIZE;
      if (columnNumber < MINI_SQUARE_SIZE){
      //   squareNumber = 4;
         columnNumber = 0;
      }
      else if (columnNumber < 2*MINI_SQUARE_SIZE){
      //   squareNumber = 5;
         columnNumber = MINI_SQUARE_SIZE;
      }
      else{
      //   squareNumber = 6;
         columnNumber = 2*MINI_SQUARE_SIZE;
      }
   }

   else{
      lineNumber = 2*MINI_SQUARE_SIZE;
      if (columnNumber < MINI_SQUARE_SIZE){
      //   squareNumber = 7;
         columnNumber = 0;
      }
      else if (columnNumber < 2*MINI_SQUARE_SIZE){
      //   squareNumber = 8;
         columnNumber = MINI_SQUARE_SIZE;
      }
      else{
      //   squareNumber = 9;
         columnNumber = 2*MINI_SQUARE_SIZE;
      }
   }

   result = TRUE;

   int squareStartLocation = columnNumber + ( SQUARE_SIZE * lineNumber);
   int k = 0;
   int squareStartLocationLineEnd;



   while (k < MINI_SQUARE_SIZE){
      squareStartLocationLineEnd = squareStartLocation + MINI_SQUARE_SIZE;
      for (i = squareStartLocation; i < squareStartLocationLineEnd; i++){
         if (game[i] != candidateDigit)
            mid_result = TRUE;
         else
            mid_result = FALSE;
         result = result && mid_result;
      }
      k++;
      squareStartLocation += SQUARE_SIZE;
      result = result && mid_result;
  }



   return result;

}

最佳答案

参数candidateDigit将作为char类型传递给isLegal()。 它一定是循环上下文导致函数始终返回 TRUE，因此您需要:

  • 向我们展示 isLegal() 的代码
  • 向我们展示 EMPTY_VALUE 的值

更新1:感谢您提供额外信息。我插入了您填写的“错误”数据，将解决方案设置为 TRUE，测试在位置 14 处停止并失败(正确的是，因为该位置包含“2”，并且同一行中还有另一个位置)。所以看来你的代码是正确的!至少就本次测试而言。

测试网格:

   sudokuGrid testGrid = {
      '6','4','2','5','3','9','8','1','7',
      '1','7','5','8','6','2','2','3','4',
      '9','3','8','1','4','7','5','9','6',
      '2','8','3','7','9','6','1','7','5',
      '5','6','4','3','8','1','3','2','8',
      '7','1','9','2','5','4','4','6','9',
      '8','2','6','4','2','3','6','5','1',
      '3','9','7','6','1','8','7','4','2',
      '4','5','1','9','7','5','9','8','3'
   };

测试输出:

isLegal(testGrid,78,9) = 0

isLegal(testGrid,0,6) = 1
isLegal(testGrid,1,4) = 1
isLegal(testGrid,2,2) = 1
isLegal(testGrid,3,5) = 1
isLegal(testGrid,4,3) = 1
isLegal(testGrid,5,9) = 1
isLegal(testGrid,6,8) = 1
isLegal(testGrid,7,1) = 1
isLegal(testGrid,8,7) = 1
isLegal(testGrid,9,1) = 1
isLegal(testGrid,10,7) = 1
isLegal(testGrid,11,5) = 1
isLegal(testGrid,12,8) = 1
isLegal(testGrid,13,6) = 1
isLegal(testGrid,14,2) = 0
                    [NOK]

注意，我所做的其他代码更改是将 isLegal() 移到它调用的函数下方(以避免默认提升返回类型)，并注释掉对 hasSolution() 和 showGrid() 的调用。

关于C 程序中的 Char 变量行为，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33634740/

上一篇：php - 在 CodeIgniter 中扩展父方法

下一篇：amazon-web-services - 如何将 AWS Signature Version 4 与 AWS Javascript SDK 结合使用从浏览器上传到 S3？

相关文章：

c - malloc 之后出现段错误 char**

c++ - 我在这里使用 "cin.get"有什么问题？

c - `typedef` 和 `struct` 在 C 函数标准内吗？

ios - 在不同的类 Objective-C 中具有相同名称的 typedef

c - C 中的 Srand 与 char 数组？

c - 在 C 中使用 for 循环时出错

java - 返回在各种语言的函数中创建的数组和对象

字符数组到无符号短转换问题

c - EOF和普通整数有什么区别？

c++ - 结构和指针 C++

©2024 IT工具网  联系我们