// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
template <class T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define endl '\n';
#define fastio ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define py cout << "YES" << endl;
#define pn cout << "NO" << endl;
#define pb push_back
#define int long long
typedef long double lld;
#define double lld
typedef long long ll;
typedef unsigned long long ull;
const ll inf = 1e18;
const ll mod = 1e9+7;
const int N = 2e5;
vector<int>primes = {2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97};
// Check for queue, priorioty_queue, stack, ordered_set solutions
// stack => LIFO (whatever goes in last comes out last)
// queue => FIFO (whatever goes in first comes out first)
// priority_queue => Dynamic queries of minimum/maximum
// ordered_set => set in vector form
//[order_of_key(k) gives number of elements less than k, while find_by_order(i) gives i^th element]
// To comment multiple lines : ctrl + /
// To find and replace : ctrl+H
void judge(){
    srand(time(NULL));
    #ifndef ONLINE_JUDGE
    freopen("1.txt","r",stdin);
    freopen("2.txt","w",stdout);
    freopen("Error.txt", "w", stderr);
    #define debug(x...) cerr << #x <<" = "; _print(x); cerr << endl;
    #else
    #define debug(x...)
    #endif
}
void usaco(string s) {
    freopen((s + ".in").c_str(),"r",stdin);
    freopen((s + ".out").c_str(),"w",stdout);
}
signed main(){
    fastio; //judge();
    int n,k; cin >> n >> k;
    vector<int>a(n);
    for(auto &x : a) cin >> x;
    vector<int>diff(n-1);
    for(int i = 0;i<n-1;i++){
        diff[i] = a[i+1] - a[i];
    }
    sort(diff.begin(),diff.end());
    int ans = k;
    for(int i = 0;i<n-k;i++){
        ans += diff[i];
    }
    cout << ans;
}
Compilation message (stderr)
stove.cpp: In function 'void judge()':
stove.cpp:37:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |     freopen("1.txt","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~
stove.cpp:38:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |     freopen("2.txt","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~
stove.cpp:39:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |     freopen("Error.txt", "w", stderr);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
stove.cpp: In function 'void usaco(std::string)':
stove.cpp:47:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |     freopen((s + ".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
stove.cpp:48:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |     freopen((s + ".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| # | Verdict  | Execution time | Memory | Grader output | 
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