851

//851
#include <cstdio>
#include <algorithm>
using namespace std;

int main(void) {
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);

    int n;
    scanf("%d", &n);
    int out[n];
    for (int i = 0; i < n; ++ i) {
        int m = 0, a;
        for (int j = 0; j < 6; ++ j) {
            scanf("%d", &a);
            if (a > m) m = a;
        }
        out[i] = m;
    }
    sort(out, out + n);
    for (int i = n - 1; i >= 0; -- i)
        printf("%d", out[i]);
    printf("\n");
    return 0;
}