59. Spiral Matrix II

class Solution {
public:
    vector<vector<int>> generateMatrix(int n) {
        vector<vector<int>> table(n);
        for(int i=0;i<n;i++)
            table[i].resize(n);
        
        int left = 0, right = n-1,up = 0,bot= n-1;
与Spiral Matrix同理

        int flag = 1;
        while(left<=right&&up<=bot&&right>=0&&bot>=0)
        {
            for(int i = left;i<=right;i++)
            {
                table[up][i]=flag;
                flag++;
            }
            up++;
            
            for(int i = up;i<=bot;i++)
            {
                table[i][right]=flag;
                flag++;
            }
            right--;
            
            for(int i=right;i>=left&&bot!=(up-1);i--)
            {
                table[bot][i]=flag;
                flag++;
            }
            bot--;
            
            for(int i=bot;i>=up&&left!=(right+1);i--)
            {
                table[i][left]=flag;
                flag++;
            }
            left++;
        }
        return table;
    }
};