/*

 Symmetry is an interesting property in the mathematical world and particularly in matrix algebra. 
 Your task is to determine if a given square matrix is symmetric.
 
 As a refresher, a matrix is a 2-dimensional array of elements. A square matrix is a matrix that 
 has the same number of rows and columns (i.e., the size is N x N). Transposition is one 
 common operation that can be performed on a matrix. In this operation, the k-th row of the 
 input matrix A becomes the k-th column in the output matrix B for all k=1,..,N.  
 The square matrix A is symmetric if it is equivalent to its transpose B; that is, A = B.
 
 The first line of the input contains the size N of the square matrix. 
 The next N lines contain N elements each, representing the elements of the matrix. 
 The output is simply "Symmetric" if the matrix is symmetric or "Not symmetric" if it is not.
 
 HINT: Transposition is really just a reflection over the main diagonal of the matrix.
 
 ====== SAMPLE RUN =======
 2
 0 2
 2 0
 Symmetric
 =========================
 
 ====== SAMPLE RUN =======
 3
 4 2 1
 2 5 3
 1 3 9
 Symmetric
 =========================
 
 ====== SAMPLE RUN =======
 3
 1 2 3
 4 5 6
 7 8 9
 Not symmetric
 =========================

*/


#include <stdio.h>
#include <stdlib.h>

int main()
{
	int n, i, j;
	int valid;

	scanf("%d", &n);

	int matrix[n][n];

	// Read in matrix
	for(i = 0; i < n; ++i)
		for(j = 0; j < n; ++j)
			scanf("%d", &matrix[i][j]);
	
	valid = 1;
	
	// Check for symmetry
	for(i = 0; valid && i < n; ++i)
		for(j = i + 1; valid && j < n; ++j)
			if(matrix[i][j] != matrix[j][i])
				valid = 0;

	if(valid)
		printf("Symmetric.\n");
	else
		printf("Not symmetric.\n");

	system("pause");
	return 0;
}