#include<iostream>
#include<vector>
#include<string>
using namespace std;

#define FOR(k,m,n) for(int (k)=(m);(k)<(n);(k)++)
#define rep(i,n) FOR((i),0,(n))

typedef long long ll;

const int INF=1e9+7;
const int MAX_N=2*1e5+5;
ll bit [MAX_N];
int n;
ll sum(int i){
	ll s=0;
	while(i>0){
		s+=bit[i];
		i-=i&-i;
	}
	return s;
}
void add(int i,int x){
	while(i<=n){
		bit[i]+=x;
		i+=i&-i;
	}
}
ll d[MAX_N];
int main(){
	ll k;
	cin>>n>>k;
	ll ans=0;
	rep(i,n){
		cin>>d[i];
		ans+=i-sum(d[i]);
		add(d[i],1);
	}
	if(k-ans>=0 && (k-ans)%2==0)cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
}