spiral matrix ii

[
 [ 1, 2, 3 ],
 [ 8, 9, 4 ],
 [ 7, 6, 5 ]
]

vector<vector<int> > generateMatrix(int n) {
    vector<vector<int> >matrix(n,vector<int>(n,0));
    int ux=0, uy=0, dx=n-1, dy=n-1;
    int count = 0;
    while(ux < dx && uy < dy){
        
        for(int i=uy; i<dy; i++){
            count++;
            matrix[ux][i] = count;
        }
        
        for(int i=ux; i<dx; i++){
            count++;
            matrix[i][dy] = count;
        }
        
        for(int i=dy; i>uy; i--){
            count++;
            matrix[dx][i] = count;
        }
        
        for(int i=dx; i>ux; i--){
            count++;
            matrix[i][uy] = count;
        }
        
        ux++;dx--;
        uy++;dy--;
    }
    
    if(ux == dx && uy == dy){
        matrix[ux][uy] = (++count);
    }
    
    return matrix;
    
}