Submission #1260475

#	Time	Username	Problem	Language	Result	Execution time	Memory
1260475		vlomaczk	Cat Exercise (JOI23_ho_t4)	C++20	41 / 100	52 ms	15940 KiB

Main

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

ll base = 1<<18;
vector<ll> t(2*base), poz(base);

void update(ll x, ll val) {
	x+=base;
	t[x] = val;
	x/=2;
	while(x > 0) {
		t[x] = max(t[x+x], t[x+x+1]);
		x/=2;
	}
}

ll query(ll a, ll b) {
	a += base-1;
	b += base+1;
	ll ans = 0;
	while(a/2 != b/2) {
		if(a%2==0) ans = max(ans, t[a+1]);
		if(b%2==1) ans = max(ans, t[b-1]);
		a/=2; b/=2;
	}
	return ans;
}

ll ans(ll a, ll b) {
	ll val = query(a, b);
	ll mid = poz[val];
	ll odp = 0;
	if(mid!=a) {
		odp = max(odp, mid-poz[query(a, mid-1)] + ans(a, mid-1));
	}
	if(mid!=b) {
		odp = max(odp, poz[query(mid+1, b)]-mid + ans(mid+1, b));
	}
	return odp;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	ll n;
	cin >> n;
	for(ll i=0; i<n; ++i) {
		ll x; cin >> x;
		poz[x] = i;
		update(i, x);
	}
	cout << ans(0, n-1) << "\n";

	return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 0 / 10
• Subtask 5: 20 / 20
• Subtask 6: 0 / 23
• Subtask 7: 0 / 26