#include"stdio.h"
#include"algorithm"
#include"vector"
#include"assert.h"
using namespace std;
vector<int> l[18], r[18];
int mat[18][18];
void left(int i, int j, int prefix) {
				if (i==j)
								l[i].push_back(prefix^mat[i][j]);
				else
								left(i, j-1, prefix^mat[i][j]),
								left(i+1, j, prefix^mat[i][j]);
}
void right(int i, int j, int prefix) {
				if (i==j)
								r[i].push_back(prefix);
				else
								right(i, j+1, prefix^mat[i][j]),
								right(i-1, j, prefix^mat[i][j]);
}
 
struct node {
				int next[2] = {0, 0};
				void fill() {
						next[0] = next[1] = 0;
				}
} trie[2000000];
int idx ;
int insert(int v, int levels) {
				if (levels == 0)
								return 0;
				int p = insert(v>>1, levels-1);
				int& next = trie[p].next[v&1];
				if(next==0)
								next = ++idx, trie[next].fill();
				return next;
}
int getBest(int v, int levels, int &p) {
				if(levels == 0)
						return p=0;
				int pNode;
				int val = getBest(v>>1, levels-1, pNode);
				p = trie[pNode].next[1-(v&1)];
				if(p)
						return val*2+1;
				p = trie[pNode].next[v&1];
				return val*2;
}
int find(vector<int> l, vector<int> r) {
				assert(l.size() == r.size());
				idx = 0;
				trie[idx].fill();
				for(int i: r)
								insert(i, 30);
				int best = 0, temp;
				for(int i: l) {
								best = max(best, getBest(i, 30, temp));
				}
				return best;
}
int main () {
		int n;
		scanf("%d", &n);
		for(int i=0; i<n; i++)
				for(int j=n; j--;)
						scanf("%d", &mat[i][j]), l[i].clear(), r[i].clear();
		left(0, n-1, 0), right(n-1, 0, 0);
		int best = 0;
		for(int i=0; i<n; i++)
						best = max(best, find(l[i], r[i]));
		printf("%d\n", best);
}