34-spirally-traversing-a-matrix.cpp

#include <bits/stdc++.h> 
using namespace std; 

 // } Driver Code Ends


class Solution
{   
public:     
    vector<int> spirallyTraverse(vector<vector<int> > matrix, int r, int c) 
    {
        int top = 0, bottom = r - 1;
        int left = 0, right = c - 1;
        int dir = 0;
        vector<int> sol;
        while(top <= bottom && left <= right)
        {
            if(dir == 0)
            {
                for(int i = left; i <= right; ++i)
                {
                    sol.push_back(matrix[top][i]);   
                }
                top += 1;
            }
            else if(dir == 1)
            {
                for(int i = top; i <= bottom; ++i)
                {
                    sol.push_back(matrix[i][right]);
                }
                right -= 1;
            }
            else if(dir == 2)
            {
                for(int i = right; i >= left; --i)
                {
                    sol.push_back(matrix[bottom][i]);
                }
                bottom -= 1;
            }
            else
            {
                for(int i = bottom; i >= top; --i)
                {
                    sol.push_back(matrix[i][left]);
                }
                left += 1;
            }
            dir = (dir + 1) % 4;
        }
        return sol;
    }
};

// { Driver Code Starts.
int main() {
    int t;
    cin>>t;
    
    while(t--) 
    {
        int r,c;
        cin>>r>>c;
        vector<vector<int> > matrix(r); 

        for(int i=0; i<r; i++)
        {
            matrix[i].assign(c, 0);
            for( int j=0; j<c; j++)
            {
                cin>>matrix[i][j];
            }
        }

        Solution ob;
        vector<int> result = ob.spirallyTraverse(matrix, r, c);
        for (int i = 0; i < result.size(); ++i)
                cout<<result[i]<<" ";
        cout<<endl;
    }
    return 0;
}  // } Driver Code Ends