打印蛇形数字

#include <iostream>
#include <iomanip>
#define MAXN 8
int a[MAXN][MAXN];

using namespace std;
int main() {
    int n, x, y, tot = 1;
    //cin >> n;
    n = 8;
    memset (a, 0, sizeof(a));
    a[x=0][y=n-1] = 1;
    while (tot < n*n) {
        //不断向下走，并且填数；先判断，再移动
        while (x+1 < n && !a[x+1][y]) a[++x][y] = ++tot;

        while (y-1 >= 0 && !a[x][y-1]) a[x][--y] = ++tot;
        while (x-1 >= 0 && !a[x-1][y]) a[--x][y] = ++tot;
        while (y+1 < n && !a[x][y+1]) a[x][++y] = ++tot;
    }
    for (x =0; x < n; x++) {
        for (y = 0; y < n; y++) {
            cout << setw(3) << a[x][y] << " ";
        }
        cout << endl;
    }
    return 0;
}