Spiral Matrix II

class Solution {public:    vector<vector<int>> generateMatrix(int n)     {        vector<vector<int>> result(n,vector<int>(n,0));        int circle = ceil(float(n)/2);        int num = 1;        for(int i = 1;i <= circle;++i)        {            for(int x = i-1;x <= n-i;++x,++num)                result[i-1][x] = num;            for(int x = i;x <= n-i;++x,++num)                result[x][n-i] = num;            for(int x = n-i-1; x >= i-1;--x,++num)                result[n-i][x] = num;            for(int x = n-i-1;x > i-1;--x,++num)                result[x][i-1] = num;        }                return result;            }};