oj.uz

Submission #925094

# Submission time Handle Problem Language Result Execution time Memory
925094 2024-02-10T18:32:22 Z ksujay2 Road Construction (JOI21_road_construction) C++17
100 / 100
 2858 ms 2013728 KB 
#include <bits/stdc++.h>
using namespace std;
const long long BSZ = 500;
struct DS {
    long long n;
    vector<long long> x, y;
    vector<vector<long long>> blocks;
    DS(vector<pair<long long, long long>>& p) {
        n = p.size();
        x.resize(n), y.resize(n);
        for(long long i = 0; i < n; i++) x[i] = p[i].first, y[i] = p[i].second;
        blocks.resize((n - 1) / BSZ + 1, vector<long long>(n, n));
        for(long long i = 0; i < n; i++) {
            blocks[i / BSZ][x[i]] = min(blocks[i / BSZ][x[i]], y[i]); 
        }
        for(long long i = 0; i < blocks.size(); i++) {
            for(long long j = 1; j < n; j++) {
                blocks[i][j] = min(blocks[i][j], blocks[i][j - 1]);
            }
        }
    }

    long long find_prev(long long i, long long lx, long long ly) {
        while(i--) {
            if(i % BSZ == BSZ - 1) {
                if(blocks[i / BSZ][lx] > ly) {
                    i -= BSZ - 1;
                    continue;
                }
            }
            if(x[i] <= lx && y[i] <= ly) return i;
        }
        return i;
    }
};

int main() {
    long long N, K; cin >> N >> K;
    vector<pair<long long, long long>> p(N);
    for(long long i = 0; i < N; i++) cin >> p[i].first >> p[i].second;
    vector<long long> sx(N), sy(N);
    for(long long i = 0; i < N; i++) sx[i] = sy[i] = i;
    sort(sx.begin(), sx.end(), [&] (long long a, long long b) { return p[a].first == p[b].first ? p[a].second < p[b].second : p[a].first < p[b].first; });
    sort(sy.begin(), sy.end(), [&] (long long a, long long b) { return p[a].second == p[b].second ? p[a].first < p[b].first : p[a].second < p[b].second; });
    vector<long long> cx(N), cy(N);
    for(long long i = 0; i < N; i++) cx[sx[i]] = cy[sy[i]] = i;
    vector<long long> o1(N), o2(N);
    for(long long i = 0; i < N; i++) o1[i] = o2[i] = i;
    sort(o1.begin(), o1.end(), [&] (long long a, long long b) { return p[a].first + p[a].second < p[b].first + p[b].second; });
    sort(o2.begin(), o2.end(), [&] (long long a, long long b) { return p[a].first - p[a].second < p[b].first - p[b].second; });
    vector<pair<long long, long long>> c1(N), c2(N);
    for(long long i = 0; i < N; i++) c1[i] = {cx[o1[i]], cy[o1[i]]}, c2[i] = {cx[o2[i]], N - 1 - cy[o2[i]]};
    DS ds1(c1), ds2(c2);
    priority_queue<pair<long long, pair<long long, long long>>> pq1;
    priority_queue<pair<long long, pair<long long, long long>>> pq2;
    auto diff1 = [&] (long long i, long long j) {
        return (p[o1[i]].first + p[o1[i]].second) - (p[o1[j]].first + p[o1[j]].second);
    };
    auto diff2 = [&] (long long i, long long j) {
        return (p[o2[i]].first - p[o2[i]].second) - (p[o2[j]].first - p[o2[j]].second);
    };
    for(long long i = 0; i < N; i++) {
        long long n1 = ds1.find_prev(i, c1[i].first, c1[i].second);
        long long n2 = ds2.find_prev(i, c2[i].first, c2[i].second);
        if(n1 != -1)
            pq1.push({-diff1(i, n1), {i, n1}});
        if(n2 != -1)
            pq2.push({-diff2(i, n2), {i, n2}});
    }
    while(K--) {
        if(pq1.size() != 0 && (pq2.size() == 0 || pq1.top().first > pq2.top().first)) {
            auto [v, ij] = pq1.top();
            cout << -v << '\n';
            pq1.pop();
            long long n1 = ds1.find_prev(ij.second, c1[ij.first].first, c1[ij.first].second);
            if(n1 != -1)
                pq1.push({-diff1(ij.first, n1), {ij.first, n1}});
        } else {
            auto [v, ij] = pq2.top();
            cout << -v << '\n';
            pq2.pop();
            long long n2 = ds2.find_prev(ij.second, c2[ij.first].first, c2[ij.first].second);
            if(n2 != -1)
                pq2.push({-diff2(ij.first, n2), {ij.first, n2}});
        }
    }
}

Compilation message

road_construction.cpp: In constructor 'DS::DS(std::vector<std::pair<long long int, long long int> >&)':
road_construction.cpp:16:32: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         for(long long i = 0; i < blocks.size(); i++) {
      |                              ~~^~~~~~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 3156 KB Output is correct
2 Correct 46 ms 3268 KB Output is correct
3 Correct 42 ms 3152 KB Output is correct
4 Correct 41 ms 3156 KB Output is correct
5 Correct 45 ms 1996 KB Output is correct
6 Correct 2 ms 604 KB Output is correct

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2116 ms 2000616 KB Output is correct
2 Correct 2065 ms 2004092 KB Output is correct
3 Correct 38 ms 2896 KB Output is correct
4 Correct 1995 ms 2004780 KB Output is correct
5 Correct 1981 ms 2003772 KB Output is correct
6 Correct 2012 ms 2004800 KB Output is correct
7 Correct 2024 ms 2004460 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2388 ms 2011152 KB Output is correct
2 Correct 2400 ms 2011024 KB Output is correct
3 Correct 0 ms 600 KB Output is correct
4 Correct 1983 ms 2004192 KB Output is correct
5 Correct 2420 ms 2011396 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2388 ms 2011152 KB Output is correct
2 Correct 2400 ms 2011024 KB Output is correct
3 Correct 0 ms 600 KB Output is correct
4 Correct 1983 ms 2004192 KB Output is correct
5 Correct 2420 ms 2011396 KB Output is correct
6 Correct 2344 ms 2011464 KB Output is correct
7 Correct 2388 ms 2011364 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 2335 ms 2011176 KB Output is correct
11 Correct 1969 ms 2003140 KB Output is correct
12 Correct 2371 ms 2011372 KB Output is correct

Subtask #5
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 3156 KB Output is correct
2 Correct 46 ms 3268 KB Output is correct
3 Correct 42 ms 3152 KB Output is correct
4 Correct 41 ms 3156 KB Output is correct
5 Correct 45 ms 1996 KB Output is correct
6 Correct 2 ms 604 KB Output is correct
7 Correct 795 ms 336312 KB Output is correct
8 Correct 771 ms 336992 KB Output is correct
9 Correct 42 ms 3156 KB Output is correct
10 Correct 577 ms 335548 KB Output is correct
11 Correct 583 ms 335640 KB Output is correct
12 Correct 689 ms 336832 KB Output is correct
13 Correct 662 ms 335380 KB Output is correct

Subtask #6
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 3156 KB Output is correct
2 Correct 46 ms 3268 KB Output is correct
3 Correct 42 ms 3152 KB Output is correct
4 Correct 41 ms 3156 KB Output is correct
5 Correct 45 ms 1996 KB Output is correct
6 Correct 2 ms 604 KB Output is correct
7 Correct 2116 ms 2000616 KB Output is correct
8 Correct 2065 ms 2004092 KB Output is correct
9 Correct 38 ms 2896 KB Output is correct
10 Correct 1995 ms 2004780 KB Output is correct
11 Correct 1981 ms 2003772 KB Output is correct
12 Correct 2012 ms 2004800 KB Output is correct
13 Correct 2024 ms 2004460 KB Output is correct
14 Correct 2388 ms 2011152 KB Output is correct
15 Correct 2400 ms 2011024 KB Output is correct
16 Correct 0 ms 600 KB Output is correct
17 Correct 1983 ms 2004192 KB Output is correct
18 Correct 2420 ms 2011396 KB Output is correct
19 Correct 2344 ms 2011464 KB Output is correct
20 Correct 2388 ms 2011364 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 2335 ms 2011176 KB Output is correct
24 Correct 1969 ms 2003140 KB Output is correct
25 Correct 2371 ms 2011372 KB Output is correct
26 Correct 795 ms 336312 KB Output is correct
27 Correct 771 ms 336992 KB Output is correct
28 Correct 42 ms 3156 KB Output is correct
29 Correct 577 ms 335548 KB Output is correct
30 Correct 583 ms 335640 KB Output is correct
31 Correct 689 ms 336832 KB Output is correct
32 Correct 662 ms 335380 KB Output is correct
33 Correct 2824 ms 2013212 KB Output is correct
34 Correct 2852 ms 2013212 KB Output is correct
35 Correct 2424 ms 2012312 KB Output is correct
36 Correct 2858 ms 2013296 KB Output is correct
37 Correct 2839 ms 2013728 KB Output is correct
38 Correct 2631 ms 2011928 KB Output is correct