#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

ll get_cnt(vector<int> &a) {
  int n = a.size();
  if (n <= 1) return 0;

  ll cnt = 0;
  vector<int> b(a.begin(), a.begin() + n / 2);
  vector<int> c(a.begin() + n / 2, a.end());

  cnt += get_cnt(b);
  cnt += get_cnt(c);

  int ai = 0, bi = 0, ci = 0;
  while (ai < n) {
    if (bi < b.size() && (ci == c.size() || b[bi] <= c[ci])) {
      a[ai++] = b[bi++];
    } else {
      cnt += n / 2 - bi;
      a[ai++] = c[ci++];
    }
  }
  return cnt;
}

int main() {
  int n;
  ll k;
  cin >> n >> k;
  vector<int> d(n);
  for (int i = 0; i < n; ++i) cin >> d[i];

  ll cnt = get_cnt(d);
  if (cnt <= k) {
    puts("YES");
  } else {
    puts("NO");
  }
  return 0;
}