DFS-深度优先遍历

#include <iostream>

/*
5 4
0 0 1 0
0 0 0 0
0 0 1 0
0 1 0 0
0 0 0 1
0 0 4 1

Total: 9 7 5
Min: 5
--------------------------------
Process exited with return value 0
Press any key to continue . . .
*/

using namespace std;

int n, m;
int minnum = 9999999;
int endy1 = 0, endy2 = 0;
int maze[20][20] = {0}, book[20][20] = {0};
int direction[4][2] = { {0, 1}, {1, 0}, {0, -1}, {-1, 0} };

void DFS(int x, int y, int step)
{
if(x == endy1 && y == endy2)
{
if(step < minnum)
{
minnum = step;
cout << minnum << " ";
}

return;
}

for(int i = 0; i <= 3; i++)
{
int tx = x + direction[i][0];
int ty = y + direction[i][1];

if(tx < 0 || tx > n - 1 || ty < 0 || ty > m - 1)
{
continue;
}

if(maze[tx][ty] == 0 && book[tx][ty] == 0)
{
book[tx][ty] = 1;
DFS(tx, ty, step + 1);
book[tx][ty] = 0;//尝试结束，取消这个点的标记
}
}

return;
}

int main()
{
cin >> n >> m;

for(int i = 0; i < n; i++)
{
for(int j = 0; j < m; j++)
{
cin >> maze[i][j];
}
}

int beginx1, beginx2;
cin >> beginx1 >> beginx2 >> endy1 >> endy2;

cout << endl << "Total: ";
DFS(beginx1, beginx2, 0);

cout << endl << "Min: " << minnum;

return 0;
}