Submission #218763

# Submission time Handle Problem Language Result Execution time Memory
218763 2020-04-02T17:22:01 Z gratus907 None (KOI16_dist) C++17
81 / 100
972 ms 4472 KB
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define usecppio ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define all(x) ((x).begin()),((x).end())
#define int ll
using pii = pair <int, int>;
#define INF 0x7f7f7f7f7f7f7f7f
const bool debug = 0;
struct point
{
    int x, y, dx, dy;
    point operator+(const point &other)
    {
        return {x+other.x, y+other.y};
    }
    point operator-(const point &other)
    {
        return {x-other.x, y-other.y};
    }
    point operator*(const int C)
    {
        return {x*C, y*C, dx, dy};
    }
    int normsq()
    {
        return x*x+y*y;
    }
};

int dist(point &a, point &b)
{
    return (a-b).normsq();
}
class convex_hull
{
public:
    int n;
    static int ccw (point &a, point &b, point &c)
    {
        int v = (b.x - a.x) * (c.y - a.y) - (b.y-a.y)*(c.x-a.x);
        if (v > 0) return 1;
        if (!v) return 0;
        return -1;
    }
    static bool compy (point &a, point &b)
    {
        if (a.y == b.y) return a.x < b.x;
        return a.y < b.y;
    }
    vector <point> pt;
    vector <point> convex;
    void graham_scan()
    {
        convex.clear();
        sort(all(pt), compy);
        point down = pt[0];
        sort(all(pt), [&down](auto a, auto b)
        {
            int u = ccw(down, a, b);
            if (u!=0) return u>0;
            else return dist(down, a) < dist(down, b);
        });
        convex.push_back(pt[0]);
        convex.push_back(pt[1]);
        for (int i = 2; i<n; i++)
        {
            while(convex.size() > 1)
            {
                point tp = convex.back();
                convex.pop_back();
                point tptp = convex.back();
                if (ccw(tptp,tp,pt[i]) > 0)
                {
                    convex.push_back(tp);
                    break;
                }
            }
            convex.push_back(pt[i]);
        }
    }
    int rotating_calipers()
    {
        int msz = 0;
        int t = 0;
        point o = {0, 0};
        int nc = convex.size();
        for (int i = 0, j = 1; i<nc; i++)
        {
            while (ccw(o, convex[i%nc], convex[j%nc]) > 0) j++;
            for (int k = j; k < j+2; k++)
            {
                int d = dist(convex[i%nc], convex[k%nc]);
                if (d > msz)
                    msz = d;
            }
        }
        return msz;
    }
};

convex_hull C;
vector <point> ptt;
int n, t;
int func(int x)
{
    C.pt.clear();
    for (int i = 0; i<n; i++)
        C.pt.push_back({ptt[i].x+ptt[i].dx*x, ptt[i].y+ptt[i].dy*x,0,0});
    C.graham_scan();
    if (debug)
    {
        printf("Time %lld information\n", x);
        for (auto it:C.convex)
            printf("%lld %lld\n",it.x, it.y);
    }
    int u = C.rotating_calipers();
    if (debug)
    {
        printf("Time %lld : Best dist %lld\n",x, u);
        printf("\n");
    }
    return u;
}
int32_t main()
{
    usecppio
    cin >> n >> t;
    C.n = n;
    for (int i = 0; i<n; i++)
    {
        int a, b, c, d;
        cin >> a >> b >> c >> d;
        ptt.push_back({a, b, c, d});
    }
    int lo = 0, hi = t;
    while(lo + 3 < hi)
    {
        int m1 = (2*lo+hi)/3;
        int m2 = (lo+2*hi)/3;
        if (func(m1) > func(m2))
            lo = m1;
        else hi = m2;
    }
    int ind = lo;
    int best = func(lo);
    for (int i = lo; i<=hi; i++)
    {
        int cur = func(i);
        if (cur < best)
        {
            best = cur;
            ind = i;
        }
    }
    cout << ind << '\n';
    cout << best << '\n';
}

Compilation message

dist.cpp: In member function 'long long int convex_hull::rotating_calipers()':
dist.cpp:89:13: warning: unused variable 't' [-Wunused-variable]
         int t = 0;
             ^
# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 30 ms 512 KB Output is correct
12 Correct 33 ms 508 KB Output is correct
13 Correct 23 ms 384 KB Output is correct
14 Correct 26 ms 512 KB Output is correct
15 Correct 25 ms 384 KB Output is correct
16 Correct 23 ms 512 KB Output is correct
17 Correct 27 ms 512 KB Output is correct
18 Correct 19 ms 512 KB Output is correct
19 Correct 20 ms 512 KB Output is correct
20 Correct 25 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 200 ms 3568 KB Output is correct
2 Correct 187 ms 3320 KB Output is correct
3 Correct 180 ms 3448 KB Output is correct
4 Correct 143 ms 4472 KB Output is correct
5 Correct 227 ms 3448 KB Output is correct
6 Correct 154 ms 4336 KB Output is correct
7 Correct 160 ms 3320 KB Output is correct
8 Correct 146 ms 3192 KB Output is correct
9 Correct 169 ms 4460 KB Output is correct
10 Correct 192 ms 3448 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 30 ms 512 KB Output is correct
12 Correct 33 ms 508 KB Output is correct
13 Correct 23 ms 384 KB Output is correct
14 Correct 26 ms 512 KB Output is correct
15 Correct 25 ms 384 KB Output is correct
16 Correct 23 ms 512 KB Output is correct
17 Correct 27 ms 512 KB Output is correct
18 Correct 19 ms 512 KB Output is correct
19 Correct 20 ms 512 KB Output is correct
20 Correct 25 ms 384 KB Output is correct
21 Correct 200 ms 3568 KB Output is correct
22 Correct 187 ms 3320 KB Output is correct
23 Correct 180 ms 3448 KB Output is correct
24 Correct 143 ms 4472 KB Output is correct
25 Correct 227 ms 3448 KB Output is correct
26 Correct 154 ms 4336 KB Output is correct
27 Correct 160 ms 3320 KB Output is correct
28 Correct 146 ms 3192 KB Output is correct
29 Correct 169 ms 4460 KB Output is correct
30 Correct 192 ms 3448 KB Output is correct
31 Correct 930 ms 3576 KB Output is correct
32 Correct 842 ms 3320 KB Output is correct
33 Correct 840 ms 3320 KB Output is correct
34 Correct 832 ms 3576 KB Output is correct
35 Correct 972 ms 3576 KB Output is correct
36 Correct 769 ms 4336 KB Output is correct
37 Correct 814 ms 3576 KB Output is correct
38 Correct 628 ms 3568 KB Output is correct
39 Correct 641 ms 3576 KB Output is correct
40 Correct 869 ms 3448 KB Output is correct
41 Incorrect 715 ms 4464 KB Output isn't correct
42 Halted 0 ms 0 KB -