#include<stdio.h>
#define MAX_ROW 5
#define MAX_COL 5
struct point {int row, col;};
/**stack***/
int top = 0;
struct point stack[512];
void push(struct point p)
{
stack[top] = p;
top++;
}
struct point pop(void)
{
top--;
return stack[top];
}
int is_empty(void)
{
return top == 0;
}
/****predecessor**/
struct point predecessor[MAX_ROW][MAX_COL] {
{ {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}}, { {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}}, { {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}}, { {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}}, { {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}, {
-1, -1}}
};
/***maze***/
int maze[MAX_ROW][MAX_COL] = {
0, 1, 0, 0, 0,
0, 1, 0, 1, 0,
0, 0, 0, 0, 0,
0, 1, 1, 1, 0,
0, 0, 0, 1, 0,
};
void visit(int row, int col, struct point pre)
{
struct point p = { row, col };
maze[row][col] = 2;
push(p);
predecessor[pre.row][pre.col] = pre;
}
int main(void)
{
struct point p = { 0, 0 };
maze[0][0] = 2;
push(p);
while (!is_empty()) {
p = pop();
if (p.row == MAX_ROW - 1 && p.cole == MAX_COL)
break;
if (p.col < MAX_COL - 1 && maze[p.row][p.col + 1] == 0) /*visit right */
visit(p.row, p.col + 1, p);
if (p.row > 0 && maze[p.row][p.col - 1]) /*visit left */
visit(p.row, p.col - 1, p);
if (p.row > 0 && maze[p.row - 1][p.col]) /*visit up */
visit(p.row - 1, p.col, p);
if (p.row < MAX_ROW - 1 && maze[p.row + 1][p.col]) /*visit down */
visit(p.row + 1, p.col,p);
}
if (p.row == MAX_ROW - 1 && p.col == MAX_COL - 1) {
while (predecessor[p.row][p.col].row != -1) {
p = predecessor[p.row][p.col];
printf("{%d,%d}", p.row, p.col);
}
} else {
printf("%s", " not path");
}
}