Problem: Little Robber Girl likes to scare animals in her zoo for fun. She decided to arrange the animals in a row in the order of non-decreasing height. However, the animals were so scared that they couldn't stay in the right places.

The robber girl was angry at first, but then she decided to arrange the animals herself. She repeatedly names numbers l and r such that r - l + 1 is even. After that animals that occupy positions between l and r inclusively are rearranged as follows: the animal at position l swaps places with the animal at position l + 1, the animal l + 2 swaps with the animal l + 3, ..., finally, the animal at position r - 1 swaps with the animal r.

Help the robber girl to arrange the animals in the order of non-decreasing height. You should name at most 20 000 segments, since otherwise the robber girl will become bored and will start scaring the animals again.

Input

The first line contains a single integer n (1 ≤ n ≤ 100) — number of animals in the robber girl's zoo.

The second line contains n space-separated integers a1, a2, ..., an (1 ≤ ai ≤ 109), where ai is the height of the animal occupying the i-th place.

Output

Print the sequence of operations that will rearrange the animals by non-decreasing height.

The output should contain several lines, i-th of the lines should contain two space-separated integers li and ri (1 ≤ li < ri ≤ n) — descriptions of segments the robber girl should name. The segments should be described in the order the operations are performed.

The number of operations should not exceed 20 000.

If the animals are arranged correctly from the start, you are allowed to output nothing.

Examples

Input

4
2 1 4 3


Output

1 4


Input

7
36 28 57 39 66 69 68


Output

1 4
6 7


Input

5
1 2 1 2 1


Output

2 5
3 4
1 4
1 4

Note

Note that you don't have to minimize the number of operations. Any solution that performs at most 20 000 operations is allowed.

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.Arrays;
import java.util.Random;

public class ProblemB {
  
  public static void main(String[] args) throws IOException {
    init();
    new ProblemB().run();
    out.flush();
    out.close();
  }
  
  static void init() throws IOException {
    in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
    out = new PrintWriter(new OutputStreamWriter(System.out));
    in.ordinaryChars(0, 65535);
    in.wordChars(0, 65535);
    in.whitespaceChars(' ', ' ');
    in.whitespaceChars('\n', '\n');
    in.whitespaceChars('\r', '\r');
  }
  
  // класс для пар
  class Pair<L, R> {
    private final L X;
    private final R Y;
    
    public Pair(L X, R Y) {
      this.X = X;
      this.Y = Y;
    }
    
    public L getX() {
      return X;
    }
    
    public R getY() {
      return Y;
    }
    
    @Override
    public int hashCode() {
      return X.hashCode() ^ Y.hashCode();
    }
    
    @Override
    public boolean equals(Object o) {
      if (!(o instanceof Pair)) return false;
      Pair pairo = (Pair) o;
      return X.equals(pairo.getX()) && Y.equals(pairo.getY());
    }
  }
  
  static final long INFL = 200000000000000000L;
  static final int INF = 2000000000;
  static final boolean DEBUG = true;
  
  static StreamTokenizer in;
  static PrintWriter out;
  
  static void print(String s) {
    print(s, 0);
  }
  
  static void print(String s, int debug) {
    if (debug == 0 || DEBUG) {
      out.print(s);
    }
  }
  
  static void println(String s) {
    println(s, 0);
  }
  
  static void println(String s, int debug) {
    if (debug == 0 || DEBUG) {
      out.println(s);
    }
  }
  
  static void printArray(int[] arr) {
    println(Arrays.toString(arr));
  }
  
  static void printArray(char[] arr) {
    println(Arrays.toString(arr));
  }
  
  static void printArray(String[] arr) {
    println(Arrays.toString(arr));
  }
  
  static void sort(int[] a) {
    Random rnd = new Random();
    for (int i = a.length - 1; i > 0; i--) {
      int index = rnd.nextInt(i);
      a[i] ^= a[index];
      a[index] ^= a[i];
      a[i] ^= a[index];
    }
    Arrays.sort(a);
  }
  
  static char[] inChars;
  static int inCharsInd;
  
  static String next() throws IOException {
    in.nextToken();
    return in.sval;
  }
  
  static char nextChar() throws IOException {
    while (inChars == null || inCharsInd >= inChars.length) {
      inChars = next().toCharArray();
      inCharsInd = 0;
    }
    return inChars[inCharsInd++];
  }
  
  static int nextInt() throws IOException {
    return Integer.valueOf(next());
  }
  
  static double nextDouble() throws IOException {
    return Double.valueOf(next());
  }
  
  static long nextLong() throws IOException {
    return Long.valueOf(next());
  }
  
  private void run() throws IOException {
    solve();
  }
  
  int K, L, M, N, P;
  
  private void solve() throws IOException {
    N = nextInt();
    int[] animal = new int[N];
    for (int i = 0; i < N; i++) {
      animal[i] = nextInt();
    }
    for (int i = 0; i < N; i++) {
      int curr = animal[i];
      int count = 0;
      for (int j = 0; j < i; j++) {
        if (animal[j] > curr) count++;
      }
      for (int j = 0; j < count; j++) {
        out.println((i - j)+ " " + ((i+1) - j));
      }
    }

  }
  
}