GFG Reverse Spiral Form of Matrix

class Solution {
  public:
    vector<int> reverseSpiral(int R, int C, vector<vector<int>>&a)  {
         vector<int> ans;
        int row=R;
        int col=C;
        int k=0;
        int r,c;
        
        while(row>=0 && col>=0)
        {
            r=k,c=k;
            while(c<col)
            {
                //cout<<"first"<<endl;
                //cout<<a[r][c]<<endl;
                ans.push_back(a[r][c]);
                ++c;
            }
            if(ans.size()==R*C)
            break;
            --c;
            r++;
            while(r<row)
            {
                //cout<<"second"<<endl;
                //cout<<a[r][c]<<endl;
                ans.push_back(a[r][c]);
                ++r;
            }
            if(ans.size()==R*C)
            break;
            
            --c;
            --r;
            while(c>=k)
            {
                //cout<<"third"<<endl;
                //cout<<a[r][c]<<endl;
                ans.push_back(a[r][c]);
                --c; 
            }
            if(ans.size()==R*C)
            break;
            c++;
            --r;
            while(r>=k+1)
            {
                //cout<<"fourth"<<endl;
                //cout<<a[r][c]<<endl;
                 ans.push_back(a[r][c]);
                --r; 
            }
            if(ans.size()==R*C)
            break;
            k++;--row;--col;
        }
        reverse(ans.begin(),ans.end());
        return ans;
    }
};