Submission #79687

#	Time	Username	Problem	Language	Result	Execution time	Memory
79687		LeMans	Aliens (IOI16_aliens)	C++14	0 / 100	3 ms	704 KiB

aliens

#include "aliens.h"
#include <stdio.h>
#include <bits/stdc++.h>

using namespace std;

typedef double db;
typedef long long ll;
typedef long double ld;
typedef unsigned int ui;
typedef unsigned long long ull;

typedef pair < db, db > pdd;
typedef pair < db, ld > pdl;
typedef pair < ld, db > pld;
typedef pair < ld, ld > ldp;

typedef pair < ll, ll > pll;
typedef pair < int, ll > pil;
typedef pair < ll, int > pli;
typedef pair < int, int > pii;

#define F first
#define S second

#define en end()
#define bg begin()

#define rev reverse
#define mp make_pair
#define pb push_back

#define y1 y1234567890
#define um unordered_map

#define all(x) x.bg, x.en
#define sz(x) (int)x.size()
#define len(x) (int)strlen(x)

#define sqr(x) ((x + 0ll) * (x))
#define sqrd(x) ((x + 0.0) * (x))

#define forn(i, n) for (int i = 1; i <= n; i++)

const ll inf = (ll)1e18;
const ll mod = (ll)1e9 + 7;

const db eps = (db)1e-9;
const db pi = acos(-1.0);

const int dx[] = {0, 0, 1, 0, -1};
const int dy[] = {0, 1, 0, -1, 0};

const int N = 100500;
const int M = 1000500;

pll line[N];
ll cur[N], dp[N];
int tot, ptr, sz, ar[N], pref[N], pos[N], f[M];

inline db cross(pll l1, pll l2) {
	return (l2.S - l1.S + 0.0) / (l1.F - l2.F);
}

inline void add(ll k, ll b) {
	while (sz >= 2) {
		if (cross(line[sz - 1], line[sz]) < cross(line[sz - 1], {k, b}))
			break;
		sz--;
	}
	line[++sz] = {k, b};
	ptr = min(ptr, sz);
}

inline ll get(ll x) {
	while (ptr < sz && cross(line[ptr], line[ptr + 1]) < x)
		ptr++;
	return line[ptr].F * x + line[ptr].S;
}

ll take_photos(int n, int m, int lim, vector < int > r, vector < int > c) {
	for (int i = 0; i < n; i++) {
		int L = min(r[i], c[i]);
		int R = max(r[i], c[i]);
		L++, R++;
		ar[++sz] = L;
		ar[++sz] = R;
		f[L] = max(f[L], R);
	}

	sort(ar + 1, ar + 1 + tot);
	tot = unique(ar + 1, ar + 1 + tot) - ar - 1;

	for (int i = 0; i <= tot; i++)
		dp[i] = cur[i] = inf;

	dp[0] = 0;

	for (int i = 1; i <= tot; i++) {
		pref[i] = max(pref[i - 1], f[ar[i]]);
		if (pref[i])
			pos[i] = lower_bound(ar + 1, ar + 1 + tot, pref[i]) - ar;
	}

	ll ans = inf;
	
	for (int j = 1; j <= lim; j++) {
		int pt = 1;
		sz = 0;
		ptr = 1;
		for (int i = 1; i <= tot; i++) {
			while (pt <= i && pos[pt - 1] <= i) {
				add(1 - ar[pt], dp[pos[pt - 1]] + sqr(ar[pt] - 1) - sqr(max(0, ar[pos[pt - 1]] - ar[pt] + 1)));
				pt++;
			}
			if (sz)
				cur[i] = min(cur[i], get((ar[i] << 1)) + sqr(ar[i]));
		}
		if (j == 1)
			assert(cur[tot] != inf);
		for (int i = 0; i <= tot; i++) {
			swap(cur[i], dp[i]);
			cur[i] = inf;
		}
		ans = min(ans, dp[tot]);
	}

	return ans;
}

• Subtask 1: 0 / 4
• Subtask 2: 0 / 12
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40