Thread: help me with this program

in this program i use the Breadth-first algorithms to solve transposition Puzzle Games, each node has four derection to move, and in the path[], i record each of the state,when the aim matrix has been found, get out of the program, but found that process into the cycle of loop and did not get out: (
some error with the red part in my program????/

Code:

#include<iostream>

using namespace std;

const int N = 3;
#define blank 0

//record every matrix in the transform path step by step to the aim
struct node {
	int nodesun[N][N];
	int pre;
	int x, y;//record the blank's place
} path[4000];


int zx[4] = { -1, 0, 1, 0 };
int zy[4] = { 0, -1, 0, 1 };
int front, rear;
int desti[N][N];//the aim matrix

//check the state of the one in the path array
int detect(struct node *p) {
	int i, j;
	for (i = 0; i < N; i++)
		for (j = 0; j < N; j++)
			if (p->nodesun[i][j] != desti[i][j])
				return 0;
	return 1;
}

//print the change state
void printlj() {
	int tempt;
	int i, j;
	tempt = rear;
	while (tempt != 0) {
		for (i = 0; i < N; i++)
			for (j = 0; j < N; j++) {
				cout << path[tempt].nodesun[i][j] << " ";
				if (j == N - 1)
					cout << endl;
			}
		tempt = path[tempt].pre;
		cout << endl;
	}
}

int main() { 
	int i, j, m, n, f;
	int ii,jj;
	int temp, find = 0;
	front = rear = 1;
	path[1].pre = 0;
	path[1].y = 2;
	path[1].x = 2;


//initialize the two matrix
/*
the begin matrix is like:
5 8 7
1 2 4
3 6 

the aim matrix is like:
1 2 3
4 5 6
7 8

*/
	int index = 0;
	int a[9] = { 5, 8, 7, 1, 2, 4, 3, 6, 0 };
	for (i = 0; i < N; i++)
		for (j = 0; j < N; j++) {
			path[1].nodesun[i][j] = a[index++];
			desti[i][j] = index;
		}

	desti[2][2] = blank;
	path[1].nodesun[2][2] = blank;

	while (front <= rear && !find) {
		m = path[front].x;
		n = path[front].y;
		for (f = 0; f < 4; f++) {
			ii = m + zx[f];
			jj = n + zy[f];
			if (ii >= 0 && ii < N && jj >= 0 && jj < N) {
				rear++;
				//path[rear] = path[front];
				for (i = 0; i < N; i++)
					for (j = 0; j < N; j++)
						path[rear].nodesun[i][j] = path[front].nodesun[i][j];
				path[rear].nodesun[m][n] = path[front].nodesun[ii][jj];
				path[rear].nodesun[ii][jj] = blank;
				path[rear].pre = front;
				path[rear].x = ii;
				path[rear].y = jj;
				if (detect(&path[rear])) {
					cout<<"find"<<endl;
					printlj();
					find = 1;
					break;
				}
			}
		}
		front++;
	}
	cout<<"end OK"<<endl;
	return 0;
}