oj.uz

Submission #31233

# Submission time Handle Problem Language Result Execution time Memory
31233 2017-08-14T16:12:56 Z leejseo None (KOI16_dist) C++
100 / 100
 283 ms 3648 KB 
#include <stdio.h>
#include <algorithm>
#include <stdlib.h>

#include <vector>

using namespace std;

#define square(a) ((a) * (long long)(a))

#define MAX_T 10000000
#define MAX_N 30000

class Star
{
        public:
                inline void read() {
                        scanf("%d%d%d%d", &m_org_x, &m_org_y, &m_dx, &m_dy);
                        m_x = m_org_x;
                        m_y = m_org_y;
                }

                inline int x() const { return m_x; }
                inline int y() const { return m_y; }

                inline void place(int t) {
                        m_x = m_org_x + t * m_dx;
                        m_y = m_org_y + t * m_dy;
                }

                inline long long distance(const Star &other) const {
                        return square(m_x - other.m_x) + square(m_y - other.m_y);
                }

        private:
                int m_org_x;
                int m_org_y;
                int m_dx;
                int m_dy;
                int m_x;
                int m_y;
};

inline long long CCW(const Star &P, const Star &P1, const Star &P2) {
        long long x1 = P.x();
        long long x2 = P1.x();
        long long x3 = P2.x();
        long long y1 = P.y();
        long long y2 = P1.y();
        long long y3 = P2.y();
        long long Area = (x2 - x1) * (y3 - y1) - (y2 - y1) * (x3 - x1);
        if (Area == 0) return 0;
        if (Area > 0) return 1;
        return -1;
}

inline bool operator<(const Star &a, const Star &b) {
        if (a.x() < b.x()) return true;
        if (a.x() > b.x()) return false;
        return a.y() < b.y();
}

inline bool check_inc_upper(vector<Star> &U, vector<Star> &L , int i, int j){
        long long a1, a2, a3, a4;
        a1 = U[i+1].y() - U[i].y();
        a2 = L[j].x() - L[j-1].x();
        a3 = L[j].y() - L[j-1].y();
        a4 = U[i+1].x() - U[i].x();
        return (a1 * a2) > (a3 * a4);
}

inline void convex_hull(Star stars[], int n, int t, vector<Star> &UP, vector<Star> &LO) {

        UP.clear();
        LO.clear();

        sort(stars, stars + n);

        for (int i = 0; i < n; i++) {
                while ((UP.size() > 1) && (CCW(UP[UP.size() - 2], UP[UP.size() - 1], stars[i]) >= 0))
                        UP.pop_back();

                while ((LO.size() > 1) && (CCW(LO[LO.size() - 2], LO[LO.size() - 1], stars[i]) <= 0))
                        LO.pop_back();

                UP.push_back(stars[i]);
                LO.push_back(stars[i]);
        }
}

inline long long farthest_distance(Star stars[], int n, int t) {

        for (int i = 0; i < n; i++)
                stars[i].place(t);

        vector<Star> UP, LO;
        convex_hull(stars, n, t, UP, LO);


        int i = 0;
        int j = LO.size() - 1;
        long long farthest = 0;
        long long dist;


        while ((i < (int)UP.size() - 1) || (j > 0)) {
                dist = UP[i].distance(LO[j]);
                if (dist > farthest) farthest = dist;

                if (i == (int)UP.size() - 1) j--;
                else if (j == 0) i++;
                else if (check_inc_upper(UP, LO, i, j)) i++;
                else j--;
        }
        dist = UP[i].distance(LO[j]);
        if (dist > farthest) farthest = dist;
        return farthest;
}

int seek_day(Star stars[], int n, int T, long long &farthest) {
        int left = 0;
        int right = T;
        while (left <= right) {
                int L = (2 * left + right)/3;
                int R = (left + 2 * right + 1)/3;
                if (farthest_distance(stars, n, L) <= farthest_distance(stars, n, R))
                        right = R - 1;
                else left = L + 1;
        }
        farthest = farthest_distance(stars, n, left);
        return left;
}

int main() {
        int n, T;
        Star stars[MAX_N];

        scanf("%d%d", &n, &T);
        for (int i=0; i<n; i++)
                stars[i].read();

        long long d;
        int day = seek_day(stars, n, T, d);

        printf("%d\n", day);
        printf("%lld\n", d);
        return 0;
}

Compilation message

dist.cpp: In function 'int main()':
dist.cpp:138:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &n, &T);
                              ^
dist.cpp: In member function 'void Star::read()':
dist.cpp:18:76: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
                         scanf("%d%d%d%d", &m_org_x, &m_org_y, &m_dx, &m_dy);
                                                                            ^

Subtask #1
2.0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 1760 KB Output is correct
2 Correct 0 ms 1756 KB Output is correct
3 Correct 0 ms 1760 KB Output is correct
4 Correct 0 ms 1760 KB Output is correct
5 Correct 0 ms 1764 KB Output is correct
6 Correct 0 ms 1760 KB Output is correct
7 Correct 0 ms 1764 KB Output is correct
8 Correct 0 ms 1756 KB Output is correct
9 Correct 0 ms 1756 KB Output is correct
10 Correct 0 ms 1760 KB Output is correct

Subtask #2
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 1760 KB Output is correct
2 Correct 0 ms 1756 KB Output is correct
3 Correct 0 ms 1760 KB Output is correct
4 Correct 0 ms 1760 KB Output is correct
5 Correct 0 ms 1764 KB Output is correct
6 Correct 0 ms 1760 KB Output is correct
7 Correct 0 ms 1764 KB Output is correct
8 Correct 0 ms 1756 KB Output is correct
9 Correct 0 ms 1756 KB Output is correct
10 Correct 0 ms 1760 KB Output is correct
11 Correct 6 ms 1756 KB Output is correct
12 Correct 6 ms 1896 KB Output is correct
13 Correct 3 ms 1760 KB Output is correct
14 Correct 6 ms 1760 KB Output is correct
15 Correct 3 ms 1764 KB Output is correct
16 Correct 3 ms 1760 KB Output is correct
17 Correct 3 ms 1764 KB Output is correct
18 Correct 3 ms 1760 KB Output is correct
19 Correct 3 ms 1764 KB Output is correct
20 Correct 6 ms 1764 KB Output is correct

Subtask #3
39.0 / 39.0

# Verdict Execution time Memory Grader output
1 Correct 43 ms 1760 KB Output is correct
2 Correct 43 ms 1764 KB Output is correct
3 Correct 53 ms 1760 KB Output is correct
4 Correct 46 ms 3120 KB Output is correct
5 Correct 29 ms 1760 KB Output is correct
6 Correct 39 ms 3120 KB Output is correct
7 Correct 43 ms 1756 KB Output is correct
8 Correct 33 ms 1760 KB Output is correct
9 Correct 49 ms 3640 KB Output is correct
10 Correct 49 ms 1764 KB Output is correct

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 1760 KB Output is correct
2 Correct 0 ms 1756 KB Output is correct
3 Correct 0 ms 1760 KB Output is correct
4 Correct 0 ms 1760 KB Output is correct
5 Correct 0 ms 1764 KB Output is correct
6 Correct 0 ms 1760 KB Output is correct
7 Correct 0 ms 1764 KB Output is correct
8 Correct 0 ms 1756 KB Output is correct
9 Correct 0 ms 1756 KB Output is correct
10 Correct 0 ms 1760 KB Output is correct
11 Correct 6 ms 1756 KB Output is correct
12 Correct 6 ms 1896 KB Output is correct
13 Correct 3 ms 1760 KB Output is correct
14 Correct 6 ms 1760 KB Output is correct
15 Correct 3 ms 1764 KB Output is correct
16 Correct 3 ms 1760 KB Output is correct
17 Correct 3 ms 1764 KB Output is correct
18 Correct 3 ms 1760 KB Output is correct
19 Correct 3 ms 1764 KB Output is correct
20 Correct 6 ms 1764 KB Output is correct
21 Correct 43 ms 1760 KB Output is correct
22 Correct 43 ms 1764 KB Output is correct
23 Correct 53 ms 1760 KB Output is correct
24 Correct 46 ms 3120 KB Output is correct
25 Correct 29 ms 1760 KB Output is correct
26 Correct 39 ms 3120 KB Output is correct
27 Correct 43 ms 1756 KB Output is correct
28 Correct 33 ms 1760 KB Output is correct
29 Correct 49 ms 3640 KB Output is correct
30 Correct 49 ms 1764 KB Output is correct
31 Correct 273 ms 1756 KB Output is correct
32 Correct 173 ms 1756 KB Output is correct
33 Correct 166 ms 1756 KB Output is correct
34 Correct 189 ms 1764 KB Output is correct
35 Correct 183 ms 1760 KB Output is correct
36 Correct 129 ms 3120 KB Output is correct
37 Correct 109 ms 1756 KB Output is correct
38 Correct 159 ms 1764 KB Output is correct
39 Correct 179 ms 1764 KB Output is correct
40 Correct 266 ms 1764 KB Output is correct
41 Correct 193 ms 3112 KB Output is correct
42 Correct 283 ms 3648 KB Output is correct