Submission #397143

# Submission time Handle Problem Language Result Execution time Memory
397143 2021-05-01T14:18:30 Z Sohsoh84 Fancy Fence (CEOI20_fancyfence) C++14
100 / 100
83 ms 4624 KB
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;

#define all(x)                      (x).begin(),(x).end()
#define X                           first
#define Y                           second
#define sep                         ' '
#define endl                        '\n'
#define debug(x)                    cerr << #x << ": " <<  x << endl;

const ll MAXN = 1e6 + 10;
const ll INF = 8e18;
const ll MOD = 1e9 + 7; // 998244353; // 1e9 + 9;
const ll INV2 = 500000004;

ll L[MAXN], H[MAXN], W[MAXN];
set<pll> st;

inline void mkey(ll& a) {
	if (a >= MOD) a -= MOD;
	if (a < 0) a += MOD;
}

inline ll C2(ll a) {
	a %= MOD;
	return a * (a - 1) % MOD * INV2 % MOD;;
} 

int main() {
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	int n;
	cin >> n;
	vector<int> v;
	for (int i = 1; i <= n; i++) {
		cin >> H[i];
		v.push_back(i);
	}

	L[0] = 1;
	ll tot = 0;
	for (int i = 1; i <= n; i++) {
		cin >> W[i];
		L[i] = L[i - 1] + W[i - 1];
		tot += W[i];
	}

	ll T = C2(tot + 1);
	st.insert({1, tot});

	sort(all(v), [] (int i, int j) {
		return H[i] < H[j];		
	});


	ll lst = 0, ans = 0;
	for (int e : v) {
		mkey(ans += T * (C2(H[e] + 1) - C2(lst + 1) + MOD) % MOD);
		ll l = L[e], r = l + W[e] - 1;
		auto it = st.upper_bound(make_pair(l, INF));
		it--;
		ll tl = it -> X, tr = it -> Y;
		mkey(T -= C2(tr - tl + 2));
		ll m_r = l - 1, m_l = r + 1;
		st.erase(it);

		if (m_r >= tl) {
			mkey(T += C2(m_r - tl + 2));
			st.insert({tl, m_r});
		} 

		if (m_l <= tr) {
			mkey(T += C2(tr - m_l + 2));
		       	st.insert({m_l, tr});	
		}

		lst = H[e];
	}

	cout << ans << endl;
	return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 23 ms 2452 KB Output is correct
4 Correct 44 ms 4036 KB Output is correct
5 Correct 53 ms 4588 KB Output is correct
6 Correct 41 ms 3628 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 4 ms 640 KB Output is correct
3 Correct 18 ms 1744 KB Output is correct
4 Correct 41 ms 3136 KB Output is correct
5 Correct 38 ms 3184 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 6 ms 588 KB Output is correct
4 Correct 19 ms 1848 KB Output is correct
5 Correct 37 ms 3148 KB Output is correct
6 Correct 38 ms 3124 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 5 ms 580 KB Output is correct
9 Correct 19 ms 1744 KB Output is correct
10 Correct 42 ms 3188 KB Output is correct
11 Correct 36 ms 3156 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 336 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 23 ms 2380 KB Output is correct
12 Correct 43 ms 3972 KB Output is correct
13 Correct 46 ms 4548 KB Output is correct
14 Correct 40 ms 3612 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 4 ms 588 KB Output is correct
17 Correct 18 ms 1744 KB Output is correct
18 Correct 37 ms 3136 KB Output is correct
19 Correct 38 ms 3248 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 4 ms 588 KB Output is correct
22 Correct 19 ms 1824 KB Output is correct
23 Correct 35 ms 3220 KB Output is correct
24 Correct 37 ms 3140 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 8 ms 716 KB Output is correct
31 Correct 9 ms 680 KB Output is correct
32 Correct 36 ms 2492 KB Output is correct
33 Correct 38 ms 2416 KB Output is correct
34 Correct 81 ms 4596 KB Output is correct
35 Correct 77 ms 4552 KB Output is correct
36 Correct 82 ms 4624 KB Output is correct
37 Correct 83 ms 4548 KB Output is correct
38 Correct 1 ms 332 KB Output is correct
39 Correct 72 ms 3396 KB Output is correct
40 Correct 53 ms 3140 KB Output is correct
41 Correct 46 ms 3212 KB Output is correct
42 Correct 35 ms 3212 KB Output is correct