#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#define UPRIGHT true
#define LEFTDOWN false

bool direction = UPRIGHT;

bool moveNext(int* i, int* j, int n) {
    if (*i == n-1 && *j == n-1) {
        return true;
    }
    if (direction == UPRIGHT) {
        if (*i == 0) {
            direction = LEFTDOWN;
            if (*j == n-1) {
                (*i)++;
            }
            else {
                (*j)++;
            }
        }
        else if (*j == n-1) {
            direction = LEFTDOWN;
            (*i)++;
        }
        else {
            (*i)--;
            (*j)++;
        }
        return false;
    }
    else {
        if (*j == 0) {
            direction = UPRIGHT;
            if (*i == n-1) {
                (*j)++;
            }
            else {
                (*i)++;
            }
        }
        else if (*i == n-1) {
            direction = UPRIGHT;
            (*j)++;
        }
        else {
            (*i)++;
            (*j)--;
        }
        return false;
    }
}

int main() {
    int *matrixPtr = NULL;
    int n = 0;
    int i = 0, j = 0;

    scanf("%d", &n);
    matrixPtr = malloc(n*n);

    for (i = 0; i < n; i++) {
        for (j = 0; j < n; j++) {
            scanf("%d", matrixPtr + i*n + j);
        }
    }

    i = 0;
    j = 0;
    while (true) {
        printf("%d ", *(matrixPtr + i*n + j));
        if (moveNext(&i, &j, n)) {
            break;
        }
    }
    printf("\n");
    return 0;
}