Problem: Gerald has n younger brothers and their number happens to be even. One day he bought n2 candy bags. One bag has one candy, one bag has two candies, one bag has three candies and so on. In fact, for each integer k from 1 to n2 he has exactly one bag with k candies. 

Help him give n bags of candies to each brother so that all brothers got the same number of candies.

Input

The single line contains a single integer n (n is even, 2 ≤ n ≤ 100) — the number of Gerald's brothers.

Output

Let's assume that Gerald indexes his brothers with numbers from 1 to n. You need to print n lines, on the i-th line print n integers — the numbers of candies in the bags for the i-th brother. Naturally, all these numbers should be distinct and be within limits from 1 to n2. You can print the numbers in the lines in any order. 

It is guaranteed that the solution exists at the given limits.

Examples

Input

2


Output

1 4
2 3

Note

The sample shows Gerald's actions if he has two brothers. In this case, his bags contain 1, 2, 3 and 4 candies. He can give the bags with 1 and 4 candies to one brother and the bags with 2 and 3 to the other brother.

Solution (in JAVA):

Solution:
/**
 * 20-11-2020
 * Created by Himanshu
 **/

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

public class A344 {
    public static void main(String[] args) throws IOException {
        PrintWriter out = new PrintWriter(System.out);
        Reader s = new Reader();
        int n = s.i();
        int [][] arr = new int[n][n];
        boolean ok = true;
        int a = 1;
        if (n%2 == 0) {
            for (int i=0;i<n;i++) {
                if (ok) {
                    for (int j=0;j<n;j++) {
                        arr[j][i] = a;
                        a++;
                    }
                    ok = false;
                } else {
                    for (int j=n-1;j>=0;j--) {
                        arr[j][i] = a ;
                        a++;
                    }
                    ok = true;
                }
            }
        } else {
            int x = 0;
            for (int i=0;i<n;i++) {
                for (int j=0;j<n;j++) {
                    arr[(j+x)%n][i] = a;
                    a++;
                }
                x++;
            }
        }
        for (int i=0;i<n;i++) {
            for (int j=0;j<n;j++) out.print(arr[i][j] + " ");
            out.println();
        }
        out.flush();
    }

    public static void shuffle(long[] arr) {
        int n = arr.length;
        Random rand = new Random();
        for (int i = 0; i < n; i++) {
            long temp = arr[i];
            int randomPos = i + rand.nextInt(n - i);
            arr[i] = arr[randomPos];
            arr[randomPos] = temp;
        }
    }

    public static long nCr(long[] fact, long[] inv, int n, int r, long mod) {
        if (n < r)
            return 0;
        return ((fact[n] * inv[n - r]) % mod * inv[r]) % mod;
    }

    private static void factorials(long[] fact, long[] inv, long mod, int n) {
        fact[0] = 1;
        inv[0] = 1;
        for (int i = 1; i <= n; ++i) {
            fact[i] = (fact[i - 1] * i) % mod;
            inv[i] = power(fact[i], mod - 2, mod);
        }
    }

    private static long power(long a, long n, long p) {
        long result = 1;
        while (n > 0) {
            if (n % 2 == 0) {
                a = (a * a) % p;
                n /= 2;
            } else {
                result = (result * a) % p;
                n--;
            }
        }
        return result;
    }

    private static long power(long a, long n) {
        long result = 1;
        while (n > 0) {
            if (n % 2 == 0) {
                a = (a * a);
                n /= 2;
            } else {
                result = (result * a);
                n--;
            }
        }
        return result;
    }

    private static long query(long[] tree, int in, int start, int end, int l, int r) {
        if (start >= l && r >= end) return tree[in];
        if (end < l || start > r) return 0;
        int mid = (start + end) / 2;
        long x = query(tree, 2 * in, start, mid, l, r);
        long y = query(tree, 2 * in + 1, mid + 1, end, l, r);
        return x + y;
    }

    private static void update(int[] arr, long[] tree, int in, int start, int end, int idx, int val) {
        if (start == end) {
            tree[in] = val;
            arr[idx] = val;
            return;
        }
        int mid = (start + end) / 2;
        if (idx > mid) update(arr, tree, 2 * in + 1, mid + 1, end, idx, val);
        else update(arr, tree, 2 * in, start, mid, idx, val);
        tree[in] = tree[2 * in] + tree[2 * in + 1];
    }

    private static void build(int[] arr, long[] tree, int in, int start, int end) {
        if (start == end) {
            tree[in] = arr[start];
            return;
        }
        int mid = (start + end) / 2;
        build(arr, tree, 2 * in, start, mid);
        build(arr, tree, 2 * in + 1, mid + 1, end);
        tree[in] = (tree[2 * in + 1] + tree[2 * in]);
    }

    static class Reader {
        private InputStream mIs;
        private byte[] buf = new byte[1024];
        private int curChar, numChars;

        public Reader() {
            this(System.in);
        }

        public Reader(InputStream is) {
            mIs = is;
        }

        public int read() {
            if (numChars == -1) throw new InputMismatchException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = mIs.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) return -1;
            }
            return buf[curChar++];
        }

        public String nextLine() {
            int c = read();
            while (isSpaceChar(c)) c = read();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isEndOfLine(c));
            return res.toString();
        }

        public String s() {
            int c = read();
            while (isSpaceChar(c)) c = read();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public long l() {
            int c = read();
            while (isSpaceChar(c)) c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9') throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int i() {
            int c = read();
            while (isSpaceChar(c)) c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9') throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public double d() throws IOException {
            return Double.parseDouble(s());
        }

        public boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public boolean isEndOfLine(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }

        public int[] arr(int n) {
            int[] ret = new int[n];
            for (int i = 0; i < n; i++) {
                ret[i] = i();
            }
            return ret;
        }

        public long[] arrLong(int n) {
            long[] ret = new long[n];
            for (int i = 0; i < n; i++) {
                ret[i] = l();
            }
            return ret;
        }
    }
//    static class pairLong implements Comparator<pairLong> {
//        long first, second;
//
//        pairLong() {
//        }
//
//        pairLong(long first, long second) {
//            this.first = first;
//            this.second = second;
//        }
//
//        @Override
//        public int compare(pairLong p1, pairLong p2) {
//            if (p1.first == p2.first) {
//                if(p1.second > p2.second) return 1;
//                else return -1;
//            }
//            if(p1.first > p2.first) return 1;
//            else return -1;
//        }
//    }
//    static class pair implements Comparator<pair> {
//        int first, second;
//
//        pair() {
//        }
//
//        pair(int first, int second) {
//            this.first = first;
//            this.second = second;
//        }
//
//        @Override
//        public int compare(pair p1, pair p2) {
//            if (p1.first == p2.first) return p1.second - p2.second;
//            return p1.first - p2.first;
//        }
//    }
}