import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Box[] boxes = new Box[n];
        for (int i = 0; i < n; i++) {
            boxes[i] = new Box(sc.nextInt(), sc.nextInt(), sc.nextInt());
        }
        Arrays.sort(boxes);
        int[] counts = new int[n];
        int max = 0;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < i; j++) {
                if (boxes[j].bigger(boxes[i])) {
                    counts[i] = Math.max(counts[i], counts[j] + 1);
                    max = Math.max(max, counts[i]);
                }
            }
        }
        System.out.println(max + 1);
    }
    
    static class Box implements Comparable<Box> {
        int[] arr = new int[3];
        
        public Box(int x, int y, int z) {
            arr[0] = x;
            arr[1] = y;
            arr[2] = z;
            Arrays.sort(arr);
        }
        
        public int compareTo(Box another) {
            return arr[0] - another.arr[0];
        }
        
        public boolean bigger(Box another) {
            for (int i = 0; i < 3; i++) {
                if (arr[i] >= another.arr[i]) {
                    return false;
                }
            }
            return true;
        }
    }
}