leetocde 59. Spiral Matrix II (模拟)

Given an integer n, generate a square matrix filled with elements from 1 to _n_2 in spiral order.

思路：仿佛回到高一的那个暑假。。。

/* ***********************************************
Author :111qqz
Created Time :2017年04月11日 星期二 18时52分15秒
File Name :59.cpp
************************************************ */
class Solution {

public:


    int ok (int dir, int &x,int &y,int n,vector<vector<int> >&res)  // 0右，1下，2左，3上
    {
	if (dir==0)
	{
	    if (y<=n-2&&res[x][y+1]==0) y++;
	    else
	    {
		dir++;
		x++;
	    }
	    return dir;
	}
	if (dir==1)
	{
	    if (x<=n-2&&res[x+1][y]==0) x++;
	    else
	    {
		dir++;
		y--;
	    }
	    return dir;
	}
	if (dir==2)
	{
	    if (y>=1&&res[x][y-1]==0) y--;
	    else
	    {
		dir++;
		x--;
	    }
	    return dir;
	}
	if (dir==3)
	{
	    if (x>=1&&res[x-1][y]==0) x--;
	    else
	    {
		dir = 0 ;
		y++;
	    }
	    return dir;
	}
    }

		
	    

    vector<vector<int>> generateMatrix(int n) {

	vector<vector<int> >res(n,vector<int>(n,0));
	int dir = 0;
	int x,y;
	x = y = 0 ;
	for ( int i = 0 ; i < n*n ; i++)
	{
	    res[x][y] = i+1;
//	    printf(" x:%d y: %d\n",x,y);
	    dir = ok (dir,x,y,n,res);
	}
	return res;


    }

};