Submission #564851

#	Time	Username	Problem	Language	Result	Execution time	Memory
564851		cheissmart	Sightseeing in Kyoto (JOI22_kyoto)	C++14	100 / 100	29 ms	3628 KiB

kyoto

#include <bits/stdc++.h>
#define IO_OP ios::sync_with_stdio(0), cin.tie(0)
#define F first
#define S second
#define V vector
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(), (v).end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;

const int INF = 1e9 + 7;

bool check(int a, int b, int c, int d) { // a / b >= c / d ?
	assert(b > 0 && d > 0);
	return 1LL * a * d >= 1LL * b * c;
}

vi go(vi a) {
	vi h;
	int n = SZ(a);
	for(int i = 0; i < n; i++) {
		while(SZ(h) >= 2 && check(a[h[SZ(h) - 1]] - a[h[SZ(h) - 2]], h[SZ(h) - 1] - h[SZ(h) - 2], a[i] - a[h[SZ(h) - 1]], i - h[SZ(h) - 1]))
			h.pop_back();
		h.PB(i);
	}
	return h;
}

signed main()
{
	IO_OP;

	int n, m;
	cin >> n >> m;
	assert(n >= 2 && m >= 2);

	vi a(n), b(m);
	for(int i = 0; i < n; i++)
		cin >> a[i];
	for(int i = 0; i < m; i++)
		cin >> b[i];

	vi ha = go(a), hb = go(b);

	ll ans = 0;

	while(SZ(ha) >= 2 || SZ(hb) >= 2) {
		if(SZ(hb) == 1 || (SZ(ha) >= 2 && check(a[ha[SZ(ha) - 1]] - a[ha[SZ(ha) - 2]], ha[SZ(ha) - 1] - ha[SZ(ha) - 2], b[hb[SZ(hb) - 1]] - b[hb[SZ(hb) - 2]], hb[SZ(hb) - 1] - hb[SZ(hb) - 2]))) {
			ans += 1LL * (ha[SZ(ha) - 1] - ha[SZ(ha) - 2]) * b[hb.back()];
			ha.pop_back();
		} else {
			ans += 1LL * (hb[SZ(hb) - 1] - hb[SZ(hb) - 2]) * a[ha.back()];
			hb.pop_back();
		}
	}

	cout << ans << '\n';


}

• Subtask 1: 10 / 10
• Subtask 2: 30 / 30
• Subtask 3: 60 / 60