import java.io.*;
import java.util.*;

public class Main {

    static int N;
    static int[] X, Y, W;

    public static void main(String[] args) {
        FastScanner sc = new FastScanner(System.in);
        N = sc.nextInt();
        X = new int[N];
        Y = new int[N];
        W = new int[N];
        for (int i = 0; i < N; i++) {
            X[i] = sc.nextInt();
            Y[i] = sc.nextInt();
            W[i] = sc.nextInt();
        }

        System.out.println(solve());
    }

    static String solve() {
        Map<Long, Integer> cords = new HashMap<>();
        for (int i = 0; i < N; i++) {
            long c = ((long)X[i] << 32) + Y[i];
            cords.put(c, i);
        }

        int max = 0;
        for (int i = 0; i < N; i++) {
            int x = X[i];
            int y = Y[i];
            int w = W[i];
            int c1 = getW(cords, x-1, y-1);
            int c2 = getW(cords, x, y-1);
            int c3 = getW(cords, x+1, y-1);
            int c4 = getW(cords, x-1, y);
            int c5 = w;
            int c6 = getW(cords, x+1, y);
            int c7 = getW(cords, x-1, y+1);
            int c8 = getW(cords, x, y+1);
            int c9 = getW(cords, x+1, y+1);

//            debug(x, y);
//            debug(c1, c2, c3, c4, c5 ,c6, c7, c8, c9);

            max = Math.max(max, c1 + c2 + c4 + c5);
            max = Math.max(max, c2 + c3 + c5 + c6);
            max = Math.max(max, c4 + c5 + c7 + c8);
            max = Math.max(max, c5 + c6 + c8 + c9);
        }
        return max + " / 1";
    }

    static int getW(Map<Long, Integer> cords, int x, int y) {
        long c = ((long)x << 32) + y;
        Integer i = cords.get(c);
        return i != null ? W[i] : 0;
    }

    @SuppressWarnings("unused")
    static class FastScanner {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        FastScanner(InputStream in) {
            reader = new BufferedReader(new InputStreamReader(in));
            tokenizer = null;
        }

        String next() {
            if (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        String nextLine() {
            if (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    return reader.readLine();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken("\n");
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        int[] nextIntArray(int n) {
            int[] a = new int[n];
            for (int i = 0; i < n; i++) a[i] = nextInt();
            return a;
        }

        int[] nextIntArray(int n, int delta) {
            int[] a = new int[n];
            for (int i = 0; i < n; i++) a[i] = nextInt() + delta;
            return a;
        }

        long[] nextLongArray(int n) {
            long[] a = new long[n];
            for (int i = 0; i < n; i++) a[i] = nextLong();
            return a;
        }
    }

    static void writeLines(int[] as) {
        PrintWriter pw = new PrintWriter(System.out);
        for (int a : as) pw.println(a);
        pw.flush();
    }

    static void writeLines(long[] as) {
        PrintWriter pw = new PrintWriter(System.out);
        for (long a : as) pw.println(a);
        pw.flush();
    }

    static void writeSingleLine(int[] as) {
        PrintWriter pw = new PrintWriter(System.out);
        for (int i = 0; i < as.length; i++) {
            if (i != 0) pw.print(" ");
            pw.print(as[i]);
        }
        pw.println();
        pw.flush();
    }

    static int max(int... as) {
        int max = Integer.MIN_VALUE;
        for (int a : as) max = Math.max(a, max);
        return max;
    }

    static int min(int... as) {
        int min = Integer.MAX_VALUE;
        for (int a : as) min = Math.min(a, min);
        return min;
    }

    static void debug(Object... args) {
        StringJoiner j = new StringJoiner(" ");
        for (Object arg : args) {
            if (arg == null) j.add("null");
            else if (arg instanceof int[]) j.add(Arrays.toString((int[]) arg));
            else if (arg instanceof long[]) j.add(Arrays.toString((long[]) arg));
            else if (arg instanceof double[]) j.add(Arrays.toString((double[]) arg));
            else if (arg instanceof Object[]) j.add(Arrays.toString((Object[]) arg));
            else j.add(arg.toString());
        }
        System.err.println(j.toString());
    }

    static void printSingleLine(int[] array) {
        PrintWriter pw = new PrintWriter(System.out);
        for (int i = 0; i < array.length; i++) {
            if (i != 0) pw.print(" ");
            pw.print(array[i]);
        }
        pw.println();
        pw.flush();
    }

    static int lowerBound(int[] array, int value) {
        int lo = 0, hi = array.length, mid;
        while (lo < hi) {
            mid = (hi + lo) / 2;
            if (array[mid] < value) lo = mid + 1;
            else hi = mid;
        }
        return lo;
    }

    static int upperBound(int[] array, int value) {
        int lo = 0, hi = array.length, mid;
        while (lo < hi) {
            mid = (hi + lo) / 2;
            if (array[mid] <= value) lo = mid + 1;
            else hi = mid;
        }
        return lo;
    }
}



Measured memory_bytes: 69640