#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
//using namespace __gnu_pbds;
using namespace std;
//typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll rand(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;
int main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
//random();
int n,t;
cin >> n >> t;
vector<pii> ans;
vector<int> arr(n+1);
rep(i,n) cin >> arr[i+1];
if(t == 1)
{
rep(i,n)
{
pii min_elm = {1e9,-1};
rep2(j,i,n-1)
{
min_elm = min(min_elm,{arr[j+1],j+1});
}
int cur = min_elm.ss;
// cout << cur << " " << min_elm.ff << " cur\n";
while(cur != i+1)
{
ans.pb({cur-1,cur});
ans.pb({cur,cur-1});
ans.pb({cur-1,cur});
swap(arr[cur-1],arr[cur]);
cur--;
}
}
}
if(t == 2)
{
for(int bit = 19; bit >= 0; bit--)
{
bool was = false;
// cout << bit << " bit\n";
rep2(i,1,n)
{
if(arr[i] & (1 << bit))
{
// cout << i << " V\n";
was = true;
int cur = i-1;
while(cur >= 1 && (arr[cur] & (1 << bit)) == 0)
{
ans.pb({cur,cur+1});
arr[cur] ^= arr[cur+1];
cur--;
}
cur = i+1;
while(cur <= n && (arr[cur] & (1 << bit)) == 0)
{
ans.pb({cur,cur-1});
arr[cur] ^= arr[cur-1];
cur++;
}
}
}
if(was)
{
rep2(i,2,n)
{
ans.pb({i-1,i});
arr[i-1] ^= arr[i];
}
}
}
}
//reverse(all(ans));
cout << siz(ans) << "\n";
forall(it,ans)
{
cout << it.ff << " " << it.ss << "\n";
}
}
