Submission #638551

#	Time	Username	Problem	Language	Result	Execution time	Memory
638551		shmad	Feast (NOI19_feast)	C++17	100 / 100	169 ms	12056 KiB

feast

#pragma GCC optimize("O3", "unroll-loops") // "Ofast" 	
#pragma GCC target("avx2", "bmi", "bmi2", "lzcnt", "popcnt") 

#include <bits/stdc++.h>

//#define int long long
#define vt vector
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define ff first
#define ss second
#define dbg(x) cerr << #x << " = " << x << '\n'
#define bit(x, i) ((x) >> (i) & 1)

using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vvt = vt< vt<int> >;

const int N = 1e6 + 5, mod = 1e9 + 7, B = 500;
const ll inf = 1e18 + 7, LIM = (1ll << 60);
const double eps = 1e-6;

int n, k;
ll a[N], p[N];
pll dp[N][2];

ll calc (ll x) {
	for (int i = 1; i <= n; i++) {
		dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]);
		ll res = dp[i - 1][0].ff - x;
		int kol = dp[i - 1][0].ss - 1;
		dp[i][1] = max(dp[i - 1][1], {res, kol});
		dp[i][1].ff += a[i];
		dp[i][1] = max(dp[i][1], {a[i], 0});
	}
	return max(dp[n][0], dp[n][1]).ss * -1;
}

bool check (ll x) {
	return (calc(x) < k);
}

void solve () {
	cin >> n >> k;
	for (int i = 1; i <= n; i++) cin >> a[i];
	ll l = 0, r = inf, ans = 0;
	while (l <= r) {
		ll mid = l + r >> 1;
		if (check(mid)) ans = mid, r = mid - 1;
		else l = mid + 1;
	}             
	calc(ans);
	cout << max(dp[n][0], dp[n][1]).ff + ans * (k - 1);
	cout << '\n';
}

bool testcases = 0;

signed main() {
#ifdef ONLINE_JUDGE
	freopen(".in", "r", stdin);
	freopen(".out", "w", stdout);
#endif
	cin.tie(0) -> sync_with_stdio(0);
	int test = 1;
	if (testcases) cin >> test;
	for (int cs = 1; cs <= test; cs++) {
		solve();
	}
}

Compilation message (stderr)

feast.cpp: In function 'void solve()':
feast.cpp:51:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   51 |   ll mid = l + r >> 1;
      |            ~~^~~

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 18 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 29 / 29