#include <bits/stdc++.h> using namespace std; #define fi first #define se second #define ll long long #ifdef LOCAL #include "algo/debug.h" #else #define debug(...) 42 #endif template <class T> bool ckmax(T &a, T b) { return a < b ? (a = b, true) : false; } template <class T> bool ckmin(T &a, T b) { return a > b ? (a = b, true) : false; } const int MAXN = 1e5 + 5; ll t[MAXN]; int main() { #define NAME "test" if (fopen(NAME".inp", "r")) { freopen(NAME".inp", "r", stdin); freopen(NAME".out", "w", stdout); } ios_base::sync_with_stdio(false); cin.tie(nullptr); int n, k; cin >> n >> k; for (int i = 1; i <= n; i++) { cin >> t[i]; } vector<ll> v; for (int i = 1; i < n; i++) { v.emplace_back(t[i + 1] - t[i] - 1); } ll ans = 0; sort(v.begin(), v.end(), greater<ll>()); for (int i = 0; i < k - 1; i++) { ans += v[i]; } cout << t[n] - t[1] - ans << '\n'; return 0; }

stove.cpp: In function 'int main()':
stove.cpp:24:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |         freopen(NAME".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
stove.cpp:25:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |         freopen(NAME".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~