#include <iostream>

using namespace std;

void traverse(int N)
{
    int i = (N-1)/2;
    int j = i;
    int dir(0);             // counter to keep track on direction
    int counter(0);         // counter
    int steps(1);           // number of steps needed per direction
    int totalSteps = N*N;   // total number of travese steps

    while (counter < totalSteps) {
        cout << i << "," << j << " ";
        
        ++counter;

        // Use direction counter to determine the direction
        switch (dir % 4) {
            case 0:
                ++i;
                break;
            case 1:
                ++j;
                // Increase the steps need for the next pivot direction
                if (counter % steps == 0)
                    ++steps;
                break;
            case 2:
                --i;
                break;
            case 3:
                --j;
                // Increase the steps need for the next pivot direction
                if (counter % steps == 0)
                    ++steps;
                break;
        }
        // Only change direction once it reach the number of steps needed per direction
        if (counter % steps == 0)
            ++dir;
    }
    cout << endl;
}

int main()
{
    traverse(3);
    traverse(5);
    traverse(7);
}