我正在使用C编程语言编写cs50课程第3周的15c项目。我有一个未定义的参考bool'win'，有人可以解释为什么会发生这种情况以及如何解决它？谢谢，这是我的代码。
/**
* fifteen.c
*
* Computer Science 50
* Problem Set 3
*
* Implements Game of Fifteen (generalized to d x d).
*
* Usage: fifteen d
*
* whereby the board's dimensions are to be d x d,
* where d must be in [DIM_MIN,DIM_MAX]
*
* Note that usleep is obsolete, but it offers more granularity than
* sleep and is simpler to use than nanosleep; `man usleep` for more.
*/
#define _XOPEN_SOURCE 500
#include <cs50.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
// constants
#define DIM_MIN 3
#define DIM_MAX 9
// board
int board[DIM_MAX][DIM_MAX];
// dimensions
int d;
// prototypes
void clear(void);
void greet(void);
void init(void);
void draw(void);
bool move(int tile);
bool won(void);
int main(int argc, string argv[])
{
// ensure proper usage
if (argc != 2)
{
printf("Usage: fifteen d\n");
return 1;
}
// ensure valid dimensions
d = atoi(argv[1]);
if (d < DIM_MIN || d > DIM_MAX)
{
printf("Board must be between %i x %i and %i x %i, inclusive.\n",
DIM_MIN, DIM_MIN, DIM_MAX, DIM_MAX);
return 2;
}
// open log
FILE* file = fopen("log.txt", "w");
if (file == NULL)
{
return 3;
}
// greet user with instructions
greet();
// initialize the board
init();
// accept moves until game is won
while (true)
{
// clear the screen
clear();
// draw the current state of the board
draw();
// log the current state of the board (for testing)
for (int i = 0; i < d; i++)
{
for (int j = 0; j < d; j++)
{
fprintf(file, "%i", board[i][j]);
if (j < d - 1)
{
fprintf(file, "|");
}
}
fprintf(file, "\n");
}
fflush(file);
// check for win
if (won())
{
printf("ftw!\n");
break;
}
// prompt for move
printf("Tile to move: ");
int tile = GetInt();
// quit if user inputs 0 (for testing)
if (tile == 0)
{
break;
}
// log move (for testing)
fprintf(file, "%i\n", tile);
fflush(file);
// move if possible, else report illegality
if (!move(tile))
{
printf("\nIllegal move.\n");
usleep(500000);
}
// sleep thread for animation's sake
usleep(500000);
}
// close log
fclose(file);
// success
return 0;
}
/**
* Clears screen using ANSI escape sequences.
*/
void clear(void)
{
printf("\033[2J");
printf("\033[%d;%dH", 0, 0);
}
/**
* Greets player.
*/
void greet(void)
{
clear();
printf("WELCOME TO GAME OF FIFTEEN\n");
usleep(2000000);
}
/**
* Initializes the game's board with tiles numbered 1 through d*d - 1
* (i.e., fills 2D array with values but does not actually print them).
*/
void init(void)
{
int tile = d * d - 1;
// row
for (int row = 0; row < d; row++)
{
// col
for (int col = 0; col < d; col++)
{
/*if (tile == 0) {
tile = atoi(placeholder);
}*/
board[row][col] = tile;
tile --;
}
}
// swap 1 and 2 if # of tiles is odd
if (d*d %2 > 0) {
board[d-1][d-3] = 1;
board[d-1][d-2] = 2;
}
}
/**
* Prints the board in its current state.
*/
void draw(void)
{
for (int row = 0; row < d; row++) {
for (int col = 0; col < d; col++) {
// if we're at 0, replace with "_"
//if ((row == d-1) && (col == d-1)) {
// printf(" _ \n");
// }
// draw the tile
//else {
printf("%2d ", board[row][col]);
//}
}
printf("\n");
}
}
/**
* If tile borders empty space, moves tile and returns true, else
* returns false.
*/
bool move(int tile)
{
// TODO
// search for tile for it's position
// set blank tile to a variable
// plus or minus one row
// plus or minus one col
/* int tile_row;
int tile_col; */
int blank_row;
int blank_col;
// find the position of the blank tile and the tile
for (int row = 0; row < d; row++) {
for (int col = 0; col < d; col++) {
/* if (board[row][col] == tile) {
tile_row = board[row];
tile_col = board[col];
} */
if (board[row][col] == 0) {
blank_row = row;
blank_col = col;
}
}
}
if (tile == board[blank_row][blank_col-1]) {
board[blank_row][blank_col] = tile;
board[blank_row][blank_col-1] = 0;
return true;
}
else if (tile == board[blank_row][blank_col+1]) {
board[blank_row][blank_col] = tile;
board[blank_row][blank_col+1] = 0;
return true;
}
else if (tile == board[blank_row-1][blank_col]) {
board[blank_row][blank_col] = tile;
board[blank_row-1][blank_col] = 0;
return true;
}
else if (tile == board[blank_row+1][blank_col]) {
board[blank_row][blank_col] = tile;
board[blank_row+1][blank_col] = 0;
return true;
}
return false;
}
/**
* Returns true if game is won (i.e., board is in winning configuration),
* else false.
*/
void save(void)
{
// log
const string log = "log.txt";
// delete existing log, if any, before first save
static bool saved = false;
if (!saved)
{
unlink(log);
saved = true;
}
// open log
FILE* p = fopen(log, "a");
if (p == NULL)
{
return;
}
// log board
fprintf(p, "{");
for (int i = 0; i < d; i++)
{
fprintf(p, "{");
for (int j = 0; j < d; j++)
{
fprintf(p, "%i", board[i][j]);
if (j < d - 1)
{
fprintf(p, ",");
}
}
fprintf(p, "}");
if (i < d - 1)
{
fprintf(p, ",");
}
}
fprintf(p, "}\n");
// close log
fclose(p);
}
答案 0 :(得分：2)
您的代码缺少函数won的实现。要修复它，请添加以下函数：
bool won(void)
{
/* Your code here */
}