#include <bits/stdc++.h>
using namespace std;
int main()
{
int n, k;
cin >> n >> k;
vector<int> p(n);
for(int i = 0; i < n; i++)
{
cin >> p[i];
}
int m = 0;
for(int i = 0; i + 1 < n; i++)
{
if(p[i + 1] != p[i] + 1)
m++;
}
m += 1;
if(m <= k)
cout << "Yes" << "\n";
else
cout << "No" << "\n";
return 0;
}
