Submission #954062

#	Time	Username	Problem	Language	Result	Execution time	Memory
954062		TAhmed33	Peru (RMI20_peru)	C++17	0 / 100	16 ms	14680 KiB

peru

#include <bits/stdc++.h>
#include <peru.h>
using namespace std;
typedef long long ll;
const ll inf = 1e16;
const int MAXN = 2'500'000 + 25;
const int MOD = 1e9 + 7;
int add (int a, int b) {
	a += b; if (a >= MOD) a -= MOD;
	return a;
}
int sub (int a, int b) {
	a -= b; if (a < 0) a += MOD;
	return a;
}
int mul (int a, int b) {
	return (a * 1ll * b) % MOD;
}
int pw[MAXN];
ll a[MAXN], n, k;
deque <array <ll, 4>> cur;
deque <ll> dd;
ll dp[MAXN];
struct MinimumStack {
	stack <pair <ll, ll>> dd;
	ll get () {
		return dd.empty() ? inf : dd.top().second;
	}
	void pop() { dd.pop(); }
	bool empty () { return dd.empty(); }
	void push (ll x) {
		ll mn = x; if (!empty()) x = min(x, get());
		dd.push({x, mn});
	}	
	int size () {
		return (int)dd.size();
	}
	ll top () { return dd.empty() ? inf : dd.top().first; }
	void swap (MinimumStack &x) {
		dd.swap(x.dd);
	}
};
struct MonotonicDeque {
	 MinimumStack left, right, temp;
	 void upd () {
	 	if (right.empty() && left.empty()) return;
	 	bool f = 0;
	 	if (right.empty()) {
	 		f = 1; left.swap(right); 
	 	}
	 	int x = (int)right.size() / 2;
	 	while (x--) {
	 		temp.push(right.top());
	 		right.pop();
	 	}
	 	while (!right.empty()) {
	 		left.push(right.top()); right.pop();
	 	}
	 	while (!temp.empty()) {
	 		right.push(temp.top()); temp.pop();
	 	}
	 	if (f) {
	 		left.swap(right);
	 	}
	 }
	 ll get () {
	 	return min(left.get(), right.get());
	 }
	 int size () {
	 	return (int)left.size() + (int)right.size();
	 }
	 bool empty() {
	 	return size() == 0;
	 }
	 void push_back (ll x) {
	 	right.push(x);
	 }
	 void pop_back() {
	 	if (right.empty()) upd();
	 	right.pop();
	 }
	 void push_front (ll x) {
	 	left.push(x);
	 }
	 void pop_front() {
	 	if (left.empty()) upd();
	 	left.pop();
	 }
	 ll back () {
	 	if (right.empty()) upd();
	 	return right.top();
	 }
	 ll front () {
	 	if (left.empty()) upd();
	 	return left.top();
	 }
} cur2;
int solve (int n, int k, int *a) {
	pw[0] = 1; for (int i = 1; i < MAXN; i++) {
		pw[i] = mul(23, pw[i - 1]);
	}
	int last = 0;
	for (int i = 1; i <= n; i++) {
		array <ll, 4> v = {i, i - 1, i - 1, dp[i - 1]};
		while (!cur.empty() && a[cur.back()[0] - 1] < a[i - 1]) {
			v[1] = cur.back()[1], v[3] = min(v[3], cur.back()[3]);
			cur.pop_back();
			cur2.pop_back();
		}
		cur.push_back(v); cur2.push_back(a[i - 1] + v[3]);
		while (!cur.empty() && cur[0][0] <= i - k) {
			cur.pop_front(); cur2.pop_front();
		}
		for (int j = last; j < cur[0][0]; j++) {
			while (!dd.empty() && dp[dd.back()] >= dp[j]) dd.pop_back(); 
			dd.push_back(j);
		}
		last = cur[0][0];
		while (!dd.empty() && dd.front() < i - k) dd.pop_front();
		cur2.pop_front();
		cur2.push_front(a[cur[0][0] - 1] + dp[dd.front()]);
		dp[i] = cur2.get();
	}
	int ret = 0;
	for (int i = 1; i <= n; i++) ret = add(ret, mul(dp[i] % MOD, pw[n - i]));
	return ret;
}

• Subtask 1: 0 / 18
• Subtask 2: 0 / 31
• Subtask 3: 0 / 51