I have got my code working but I can\'t figure out how to remove the \" fin = fo
ID: 3544335 • Letter: I
Question
I have got my code working but I can't figure out how to remove the " fin = fopen("maze.in", "r"); " line from my code without messing up the output results. Please go through my code and correct the problem. This should be really quick.
The code MUST LAUNCH THROUGH COMMAND PROMPT
The name of the input file should be not related to the C Code what so ever. Anyone should be able to type in ANY file name and get the correct results listed in the output file Sample.
maze.exe < AnyFileName.in
There can be NO "fscanf" OR '"fprintf"
SAMPLE INPUT FILE:
===================
2
3 3
~~~
~S~
~~~
5 6
~~~~~~
~XXXX~
~XS-X~
~-XX-~
~~~~~~
===================
Sample OUTPUT File:
====================
1
-1
====================
MY COMPLETED AND WORKING CODE: I need you to fix the problem LISTED ABOVE!!!
SAVE AS A C FILE NOT A C++
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
const char BORDER = '~';
const char EMPTY = '-';
const char START = 'S';
const char BLOCK = 'X';
const int NOT_VISITED = -1;
typedef struct CoordStruct { int r, c; } Coord;
typedef struct CoordQueueStruct {
Coord* contents;
int cap;
int count;
int front;
} CoordQueue;
int shortestDistance(FILE *fin);
int main(int argc, char* argv[])
{
FILE *fin;
FILE *fout;
int testCount;
char filePath[100];
// Open input file
fin = fopen("maze.in", "r");
if (!fin) // handle file not found error
{
puts("Cannot open file. Program aborted.");
return 1;
}
// Find shortest distances
fscanf(fin, "%d", &testCount);
while (testCount--)
printf("%d ", shortestDistance(fin));
//fprintf(fout, "%d ", shortestDistance(fin));
//fclose(fout);
fclose(fin);
return 0;
}
void init(CoordQueue *q)
{
q->cap = 8;
q->contents = (Coord*)malloc(sizeof(Coord)*q->cap);
q->count = 0;
q->front = 0;
}
void doubleCapacity(CoordQueue *q)
{
int newCap = 2*q->cap;
Coord* newContents = (Coord*)malloc(sizeof(Coord)*newCap);
int i = 0;
while (i < q->count)
newContents[i++] = q->contents[(q->front++)%q->cap];
q->front = 0;
free(q->contents);
q->cap = newCap;
q->contents = newContents;
}
void enqueue(CoordQueue *q, int r, int c)
{
if (q->count == q->cap) doubleCapacity(q);
Coord p;
p.r = r, p.c = c;
q->contents[(q->front + q->count) % q->cap] = p;
++q->count;
}
void dequeue(CoordQueue *q, int *r, int *c)
{
if (r) *r = q->contents[q->front].r;
if (c) *c = q->contents[q->front].c;
if (++q->front >= q->cap) q->front -= q->cap;
--q->count;
}
int getNonWhiteSpaceChar(FILE *fin)
{
int c = fgetc(fin);
while (isspace(c)) c = fgetc(fin);
return c;
}
int shortestDistance(FILE *fin)
{
int row, col;
char** maze = NULL; //maze 2D array
int** dist = NULL; //distance 2D array
CoordQueue q;
int shortestDist = -1;
int r, c;
// Get maze dimensions
fscanf(fin, "%d%d", &row, &col);
// Initialize empty queue
init(&q);
// Allocate memory for maze 2D array and dist 2D array
// Init dist 2D array NOT_VISITED
maze = (char**)malloc(sizeof(char*)*row);
dist = (int **)malloc(sizeof(int *)*row);
for (r = 0; r < row; ++r)
{
maze[r] = (char*)malloc(sizeof(char)*col);
dist[r] = (int *)malloc(sizeof(int) *col);
for (c = 0; c < col; ++c) { dist[r][c] = NOT_VISITED; }
}
// Fill maze and set starting position to dist, q
for (r = 0; r < row; ++r)
for (c = 0; c < col; ++c)
{
maze[r][c] = getNonWhiteSpaceChar(fin);
if (maze[r][c] == START)
{
dist[r][c] = 0;
enqueue(&q, r, c);
}
}
// Solve using BFS
while (q.count)
{
// Retrieve the front Coord in q
dequeue(&q, &r, &c);
// If any of top, bottom, left, right square is BORDER,
//we have reached the border, break out of the loop and set
//shortestDist to current square distance + 1
if (maze[r-1][c] == BORDER || maze[r+1][c] == BORDER ||
maze[r][c-1] == BORDER || maze[r][c+1] == BORDER)
{
shortestDist = dist[r][c] + 1;
break;
}
// Check top square
if (maze[r-1][c] != BLOCK && dist[r-1][c] == NOT_VISITED)
{
dist[r-1][c] = dist[r][c] + 1;
enqueue(&q, r-1, c);
}
// Check bottom square
if (maze[r+1][c] != BLOCK && dist[r+1][c] == NOT_VISITED)
{
dist[r+1][c] = dist[r][c] + 1;
enqueue(&q, r+1, c);
}
// Check left square
if (maze[r][c-1] != BLOCK && dist[r][c-1] == NOT_VISITED)
{
dist[r][c-1] = dist[r][c] + 1;
enqueue(&q, r, c-1);
}
// Check right square
if (maze[r][c+1] != BLOCK && dist[r][c+1] == NOT_VISITED)
{
dist[r][c+1] = dist[r][c] + 1;
enqueue(&q, r, c+1);
}
}
// Free maze 2D array, dist 2D array, and queue q
for (r = 0; r < row; ++r)
{
free(maze[r]);
free(dist[r]);
}
free(maze);
free(dist);
free(q.contents);
return shortestDist;
}
Explanation / Answer
// Solve using BFS
while (q.count)
{
// Retrieve the front Coord in q
dequeue(&q, &r, &c);
// If any of top, bottom, left, right square is BORDER,
//we have reached the border, break out of the loop and set
//shortestDist to current square distance + 1
if (maze[r-1][c] == BORDER || maze[r+1][c] == BORDER ||
maze[r][c-1] == BORDER || maze[r][c+1] == BORDER)
{
shortestDist = dist[r][c] + 1;
break;
}
// Check top square
if (maze[r-1][c] != BLOCK && dist[r-1][c] == NOT_VISITED)
{
dist[r-1][c] = dist[r][c] + 1;
enqueue(&q, r-1, c);
}
// Check bottom square
if (maze[r+1][c] != BLOCK && dist[r+1][c] == NOT_VISITED)
{
dist[r+1][c] = dist[r][c] + 1;
enqueue(&q, r+1, c);
}
// Check left square
if (maze[r][c-1] != BLOCK && dist[r][c-1] == NOT_VISITED)
{
dist[r][c-1] = dist[r][c] + 1;
enqueue(&q, r, c-1);
}
// Check right square
if (maze[r][c+1] != BLOCK && dist[r][c+1] == NOT_VISITED)
{
dist[r][c+1] = dist[r][c] + 1;
enqueue(&q, r, c+1);
}
}
// Free maze 2D array, dist 2D array, and queue q
for (r = 0; r < row; ++r)
{
free(maze[r]);
free(dist[r]);
}
free(maze);
free(dist);
free(q.contents);
return shortestDist;
}