#include "bits/stdc++.h"
using namespace std;
#define int long long
signed main () {
int n, s;
cin >> n >> s;
vector <int> a(n);
for (int i = 0; i < n; i ++) cin >> a[i];
vector <pair <int, int>> v;
while (!is_sorted(a.begin(), a.end())) {
for (int i = 1; i < n; i ++) {
if (a[i - 1] < a[i]) continue;
if ((a[i - 1] ^ a[i]) < a[i]) a[i - 1] ^= a[i], v.push_back({i - 1, i});
else a[i] ^= a[i - 1], v.push_back({i, i - 1});
}
//for (int i = 0; i < n; i ++) cout << a[i] << ' ';
//cout << endl;
}
cout << v.size() << endl;
for (int i = 0; i < (int)v.size(); i ++) cout << v[i].first + 1 << ' ' << v[i].second + 1 << endl;
return 0;
}
