Array Traversal In Spiral Order

// Author: madhukesh
// Created: 2021-05-11 23:25:18

/*Success isn't permanent, failure isn't fatal,
it's the courage to continue that counts.*/

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

vector<int> spiralOrder(const vector<vector<int> > &A)
{
    vector<int>ans;

    int n=A.size();
    if(n==0)
        return ans;
    int m=A[0].size();

    int l=0,r=m-1,u=0,d=n-1;

    int dir=0;

    while((l<=r)&&(u<=d))
    {
        if(dir==0)
        {
            for(int i=l;i<=r;i++)
                ans.push_back(A[u][i]);
            u++;
        }
        else if(dir==1)
        {
            for(int i=u;i<=d;i++)
                ans.push_back(A[i][r]);
            r--;
        }
        else if(dir==2)
        {
            for(int i=r;i>=l;i--)
                ans.push_back(A[d][i]);
            d--;
        }
        else
        {
            for(int i=d;i>=u;i--)
                ans.push_back(A[i][l]);
            l++;
        }
        dir=(dir+1)%4;
    }
    return ans;
}


void solve()
{
    int n,m;
    cin>>n>>m;

    vector<vector<int>>arr(n,vector<int>(m,0));

    for(int i=0;i<n;i++)
    {
        for(int j=0;j<m;j++)
            cin>>arr[i][j];
    }

    vector<int>ans=spiralOrder(arr);

    for(int i=0;i<ans.size();i++)
        cout<<ans[i]<<" ";


    return;
}

int main()
{
    int t=1;
    //sfi(t)

    while(t--)
        solve();

    return 0;
}