Submission #610270

#	Time	Username	Problem	Language	Result	Execution time	Memory
610270		Arnch	Fancy Fence (CEOI20_fancyfence)	C++17	12 / 100	300 ms	262144 KiB

fancyfence

// oooo
/*
 har chi delet mikhad bebar ~
 gitar o ba khodet nabar! ~
 ;Amoo_Hasan;
*/

#include<bits/stdc++.h>
//#pragma GCC optimize("O3,no-stack-protector,unroll-loops")
//#pragma GCC target("avx2,fma")

using namespace std;

typedef long long ll;
typedef long double ld;

#define Sz(x) int((x).size())
#define All(x) (x).begin(), (x).end()
#define wtf(x) cout<<#x <<" : " <<x <<endl

constexpr ll inf = 1e18, N = 1e6 + 10, mod = 1e9 + 7, pr = 1000696969;

int h[N], w[N];
ll bpow;
vector<int> vc;

ll poww(ll x, int y) {
	ll res = 1;
	for(; y; y /= 2, x = x * x % mod)
		if(y & 1)
			res *= x, res %= mod;
	return res;
}
ll choose(ll x) {
	ll res = x * (x - 1) % mod;
	res *= bpow;
	res %= mod;
	return res;
}

int main() {
    ios :: sync_with_stdio(0), cin.tie(0);

	bpow = poww(2, mod - 2);

	int n; cin >>n;
	for(int i = 0; i < n; i++) {
		cin >>h[i];
	}
	for(int i = 0; i < n; i++) {
		cin >>w[i];
		for(int j = 0; j < w[i]; j++) {
			vc.push_back(h[i]);
		}
	}

	ll ans = 0;
	for(int i = 0; i < Sz(vc); i++)
		for(int j = i; j < Sz(vc); j++) {
			int cnt = min(vc[i], vc[j]) + 1;
			for(int k = i + 1; k < j; k++) {
				cnt = min(cnt, vc[k] + 1);
			}
			cnt = choose(cnt);
			ans += cnt, ans %= mod;
		}

	cout<<ans;

    return 0;
}

• Subtask 1: 0 / 0
• Subtask 2: 12 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27