import java.util.*;

public class MaxNetVulnerability {
    static int getMaxNetVulnerability(List<List<Integer>> vulnerability) {
        int n = vulnerability.size();
        int m = vulnerability.get(0).size();

        int maxNetVulnerability = Integer.MIN_VALUE;

        for (int row1 = 0; row1 < n; row1++) {
            for (int row2 = row1 + 1; row2 < n; row2++) {
                List<Integer> row1Data = vulnerability.get(row1);
                List<Integer> row2Data = vulnerability.get(row2);

                int[] maxInColumns = new int[m];

                for (int col = 0; col < m; col++) {
                    int max = Math.max(row1Data.get(col), row2Data.get(col));
                    maxInColumns[col] = max;
                }

                int minMaxInColumns = Integer.MAX_VALUE;
                for (int max : maxInColumns) {
                    minMaxInColumns = Math.min(minMaxInColumns, max);
                }

                maxNetVulnerability = Math.max(maxNetVulnerability, minMaxInColumns);
            }
        }

        return maxNetVulnerability;
    }

    public static void main(String[] args) {
        List<List<Integer>> vulnerability = new ArrayList<>();
        vulnerability.add(Arrays.asList(1, 3, 1));
        vulnerability.add(Arrays.asList(3, 1, 1));
        vulnerability.add(Arrays.asList(1, 2, 2));
        vulnerability.add(Arrays.asList(1, 1, 3));

        int maxVulnerability = getMaxNetVulnerability(vulnerability);
        System.out.println("Maximum possible net vulnerability: " + maxVulnerability);
    }
}