#include <bits/stdc++.h> #define _ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); #define fore(i,a,b) for(lli i = (a), abcdxd = (b); i < abcdxd; i++) #define f first #define s second #define pb push_back #define ENDL '\n' #define sz(v) lli((v).size()) #define all(v) (v).begin(), (v).end() #define rall(v) (v).rbegin(), (v).rend() using namespace std; typedef long long lli; typedef vector<lli> vi; typedef pair<lli,lli> ii; typedef vector<ii> vii; typedef long double ld; #define deb(x) cout << #x << ": " << x << ENDL; int main(){ _ lli n, k; cin >> n >> k; vi v; lli ans = 1ll; { vi b(n); for (auto & i : b) cin >> i; sort(all(b)); fore(i,1,n){ if (b[i] == b[i - 1]) continue; ans++; v.pb(b[i] - (b[i - 1] + 1ll)); } } sort(all(v)); fore(i,0,max(0ll, sz(v) - k + 1ll)) ans += v[i]; cout << ans << ENDL; return 0; }