#include <bits/stdc++.h>
#pragma optimization_level 3
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx")
using namespace std;
const long long N = 5e5 + 5;
const long long mod = 998244353;
const long long INF = 1e18;
const int INFi = 0x7f7f7f7f;
long long test = 1, n, a[N];
vector<pair<long long, long long> > ans;
vector<long long> inv[N];
void solve() {
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> a[i];
  for (int i = 1; i <= n; i++) {
    for (int j = i + 1; j <= n; j++) {
      if (a[j] < a[i]) inv[j].push_back(i);
    }
  }
  for (int i = N; i > 0; i--) {
    set<pair<long long, long long> > second;
    for (auto it : inv[i]) second.insert({a[it], it});
    for (auto it : second) ans.push_back({it.second, i});
  }
  cout << ans.size() << "\n";
  for (auto it : ans) cout << it.first << " " << it.second << "\n";
  ;
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cout << fixed;
  cout << setprecision(10);
  ;
  for (int i = 1; i <= test; i++) {
    solve();
  }
}
