Submission #647761

#	Time	Username	Problem	Language	Result	Execution time	Memory
647761		x0r	K blocks (IZhO14_blocks)	C++17	100 / 100	240 ms	41980 KiB

blocks

#pragma GCC optimize ("O2")
#include <bits/stdc++.h>

#define ll long long
#define ld long double
#define fi first 
#define se second
#define pll pair < ll, ll >
#define pii pair < int, int >
#define fast ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);

using namespace std;

const string NAME = "";
const string NAME2 = "TEST";
const ld ESP = 1e-9;
const ll INF = 1e9 + 7;
const ll LINF = 1E18;
const ll nmax = 2e5;
const ll MOD = 1e9 + 7;
const ll base = 2309;

void fre() {
	string finp = NAME + ".inp";
	string fout = NAME + ".out";
	freopen(finp.c_str(), "r", stdin);
	freopen(fout.c_str(), "w", stdout);
}

int n, k, a[100003], dp[100003][103];

int main() {
	fast;
	cin >> n >> k;
	for (int i = 1; i <= n; i++) cin >> a[i];
	memset(dp, 64, sizeof(dp));
	dp[1][1] = a[1];
	for (int i = 2; i <= n; i++) 
		dp[i][1] = max(dp[i - 1][1], a[i]);
	for (int j = 2; j <= k; j++) {
		stack < pii > st;
		for (int i = 1; i <= n; i++) {
			int val = dp[i - 1][j - 1], l;
			while (st.size() && a[i] >= a[st.top().se]) {
				val = min(val, st.top().fi);
				st.pop();
			}
			if (st.size()) l = st.top().se;
			else l = 0;
			st.push({val, i});
			dp[i][j] = min(dp[l][j], val + a[i]);
		}
	}
	cout << dp[n][k];
}

Compilation message (stderr)

blocks.cpp: In function 'void fre()':
blocks.cpp:26:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |  freopen(finp.c_str(), "r", stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:27:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |  freopen(fout.c_str(), "w", stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 18 / 18
• Subtask 3: 21 / 21
• Subtask 4: 47 / 47