#include <bits/stdc++.h>
#define rep(i,n) for(int i=(0);i<(n);i++)

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

// class
const int max_n  = 202020;

class BinaryIndexedTree{

private:
	int n;
	ll bit[max_n];

public:
	BinaryIndexedTree(int n){
		this -> n = n;
	}

    ll sum(int i){
        ll s = 0;
        while(i > 0){
            s += bit[i];
            i -= i & (-i);
        }
        return s;
    }

    void add(int i, ll x){
        while(i <= n){
            bit[i] += x;
            i += i & (-i);
        }
    }
};

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);

	ll n, k;
	cin >> n >> k;

	vector<int> a(n);
	rep(i, n) cin >> a[i];

	BinaryIndexedTree bit(n);
	ll ans = 0ll;
	for(ll i = 0; i < n; i++){
		ans += i - bit.sum(a[i]);
		bit.add(a[i], 1ll);
	}

	if(ans == k || (ans <= k && (ans % 2 == k % 2))){
		cout << "YES" << endl;
	}else{
		cout << "NO" << endl;
	}

}