c - 如何扫描网格以仅替换某个字符？

Question

我想要一个在将所有 CSHIPS ('.') 更改为 REVEALEDCSHIPS ('C') 并显示它们后结束我的程序的函数。
问题是所有 SEA 方 block 也都变成了 REVEALEDCSHIPS，但当然应该保留 SEA。
SEA 的值也定义为“.”，如果这有区别的话。
在下面找到我的代码环境。

#include<stdio.h>
#include<time.h>
#include<stdlib.h>
#include<strings.h>

#define MAXGRIDSIZE 15
#define SEA '.'
#define PSHIP 'P'
#define SUNKENPSHIP 'B'
#define CSHIP '.'
#define BOMB '*'
#define SUNKENCSHIP 'V'
#define REVEALEDCSHIP 'C'
unsigned char grid[MAXGRIDSIZE][MAXGRIDSIZE];
int fleetSize;
void initGrid()
{
    int x, y;
    for(y=0; y<MAXGRIDSIZE; y++)
    {
        for(x=0; x<MAXGRIDSIZE; x++)
        {
            grid[y][x] = SEA;
        }
    }
}
void printGrid()
{
    int x, y;
    printf("\n");
    for(y=0; y<MAXGRIDSIZE; y++)
    {
        printf("%2d", y);
        for(x=0; x<MAXGRIDSIZE; x++)
        {
            printf("%3c", grid[y][x]);
        }
        printf("\n");
    }
    printf("%2c", ' ');
    for(x=0; x<MAXGRIDSIZE; x++)
    {
            printf("%3d", x);
    }
    printf("\n");
}
void placePShip()
{
    int x,y;
    printf("\nEnter Ship location: x , y: ");
    scanf("%d , %d", &x, &y);
    if (grid[y][x] == SEA)
    {
        grid[y][x] = PSHIP;
    }
}
void placeCShip(){
    srand(time(NULL));
    while ( 1 )
    {
        int a=rand()%15 ;
        int b=rand()%15 ;
        if (grid[a][b] == SEA)
        {
            grid[a][b] = CSHIP;
            break ;
        }
    }
}
void placeShips()
{
    int i;
    printf("\nEnter fleet size : ");
    scanf("%d", &fleetSize);
    if(fleetSize>122)
    {
        printf("\nThat size is too large to fit in grid, select a smaller number");
        placeShips();
        return;
    }
    for(i=0;i<fleetSize;i++)
    {
        placePShip();
        placeCShip();
        printGrid();        
    }
}
void quit()
{
    int x,y;
    for(y=0;y<MAXGRIDSIZE;y++)
    {
        if(grid[y][x] == CSHIP){grid[y][x] = REVEALEDCSHIP;}
        for(x=0;x<MAXGRIDSIZE;x++)
        {
            if(grid[y][x] == CSHIP)
            {
                grid[y][x] = REVEALEDCSHIP;
            }
        }
    }
    printGrid();
    printf("\n>>GG, here are all remaining ships");
}
int main()
{
    initGrid();
    printGrid();
    placeShips();
    quit();
}

Answer 1

您需要对 SEA 和 CSHIP 使用不同的值；
因为对相同的值使用不同的名称/同义词/宏没有帮助。
任何与 CSHIP 相同的内容(被定义为 '.')也将与 SEA 相同(也被定义为 '.')，因此代码将做出以下 react : SEA和CSHIP就像CSHIP一样，即将SEA变成REVEALEDCSHIP。

#define SEA '.'
/* this one gets shown to the player directly */

#define CSHIP 'H' 
/* this one needs to be kept secret from the player during game, see below */

为了使它们在游戏过程中对玩家来说看起来相同(在 quit() 中显示它们之前)，请更改 printGrid() 函数以显示它们相同，但知道差异:

void printGrid()
{
    int x, y;
    printf("\n");
    for(y=0; y<MAXGRIDSIZE; y++)
    {
        printf("%2d", y);
        for(x=0; x<MAXGRIDSIZE; x++)
        {
            if(CSHIP == grid[y][x])   /* do not show like this */
            {    printf("%3c", SEA);  /*   camouflage instead  */
            } else
            {    printf("%3c", grid[y][x]); /* others directly */
            }
        }
        printf("\n");
    }
    printf("%2c", ' ');
    for(x=0; x<MAXGRIDSIZE; x++)
    {
            printf("%3d", x);
    }
    printf("\n");
}

然后你的 quit() 函数应该可以工作，这里只是一些清理工作:

void quit()
{
    /* always init, just for safety */
    int x=0;
    int y=0;

    for(y=0;y<MAXGRIDSIZE;y++)
    {
        /*  unneeded, and did use previously non-initialised x
            if(grid[y][x] == CSHIP){grid[y][x] = REVEALEDCSHIP;}
         */
        for(x=0;x<MAXGRIDSIZE;x++)
        {
            if(grid[y][x] == CSHIP)
            {
                grid[y][x] = REVEALEDCSHIP;
            }
        }
    }
    printGrid();
    printf("\n>>GG, here are all remaining ships.\n"); /* newline, to ensure output */
}