oj.uz

Submission #884477

# Submission time Handle Problem Language Result Execution time Memory
884477 2023-12-07T13:09:06 Z AnhPham Palembang Bridges (APIO15_bridge) C++17
31 / 100
 33 ms 3832 KB 
#include <bits/stdc++.h>

#ifdef OP_DEBUG
    #include <algo/debug.h>
#else
    #define debug(...) 26
#endif

using namespace std;

#define int 	long long // maybe tle?
#define sz(v)   (int)(v).size()
#define all(v)  (v).begin(), (v).end()
#define TcT     template <class T

const   int     MOD = (int)1e9 + 7, INF = (int)2e9 + 9, INF64 = (int)4e18 + 18;

TcT>            bool minimize(T &val, const T &upd) { return upd < val ? val = upd, 1 : 0; }
TcT>            bool maximize(T &val, const T &upd) { return upd > val ? val = upd, 1 : 0; }

TcT, class S>   istream &operator >> (istream &scanf, pair <T, S> &u) { return scanf >> u.first >> u.second;        }
TcT, class S>   ostream &operator << (ostream &print, pair <T, S> &u) { return print << u.first << ' ' << u.second; }

void solve();

int32_t main() {
    cin.tie(nullptr), cout.tie(nullptr) -> sync_with_stdio(0);
    int testcases = 1;

#define TC 0
    if (TC) { cin >> testcases; } for (; testcases--;) { solve(); }
}

/* [Pham Hung Anh - 11I - Tran Hung Dao High School for Gifted Student] */

int k, n;
int same_side;
vector <int> buildings;
vector <pair <int, int>> opposite;

namespace sub12 { // O(n)
    void solve() {
        int ans = same_side;
        if (sz(buildings) == 0)
            return void(cout << ans << '\n');

        int m = sz(buildings);
        int median = buildings[(m + 1) / 2];

        for (int i = 0; i < m; ++i)
            ans += abs(median - buildings[i]);
        
        cout << ans + sz(buildings) / 2 << '\n';
    }
}

namespace sub3 { // O(n^3)
    void solve() {
        int ans = same_side;
        if (sz(buildings) == 0)
            return void(cout << ans << '\n');

        int res = INF64;
        for (int i = 0; i < sz(buildings); ++i)
            for (int j = i + 1; j < sz(buildings); ++j) {
                int bridge1 = buildings[i], bridge2 = buildings[j];
                int sum = 0;
                for (auto p : opposite)
                    sum += min(abs(p.first - bridge1) + abs(p.second - bridge1), abs(p.first - bridge2) + abs(p.second - bridge2)) + 1;
                
                minimize(res, sum);
            }
            
        cout << ans + res << '\n';
    }
}

namespace sub4 { // O(log3(n)^2 * n)
    int get(int bridge1, int bridge2) {
        int sum = same_side;
        for (auto p : opposite)
            sum += min(abs(p.first - bridge1) + abs(p.second - bridge1), abs(p.first - bridge2) + abs(p.second - bridge2)) + 1;
        
        return sum;
    }

    int ternary_search(int bridge1) {
        int res = INF64;
        int lo = bridge1 + 1, hi = sz(buildings) - 1;

        while (lo <= hi) {
            int mid1 = lo + (hi - lo) / 3;
            int mid2 = hi - (hi - lo) / 3;

            int sum1 = get(buildings[bridge1], buildings[mid1]);
            int sum2 = get(buildings[bridge1], buildings[mid2]);
            minimize(res, min(sum1, sum2));

            if (sum1 < sum2)
                hi = mid2 - 1;
            else if (sum1 > sum2)
                lo = mid1 + 1;
            else
                lo = mid1 + 1, hi = mid2 - 1;
        }

        return res;
    }

    void solve() {
        int ans = INF64;
        int lo = 0, hi = sz(buildings) - 2;
        
        while (lo <= hi) {
            int mid1 = lo + (hi - lo) / 3;
            int mid2 = hi - (hi - lo) / 3;
            
            int ans1 = ternary_search(mid1);
            int ans2 = ternary_search(mid2);
            minimize(ans, min(ans1, ans2));

            if (ans1 < ans2)
                hi = mid2 - 1;
            else if (ans1 > ans2)
                lo = mid1 + 1;
            else
                lo = mid1 + 1, hi = mid2 - 1;
        }

        cout << ans << '\n';
    }
}

namespace sub5 {
    int suml = 0, sumr = 0;
    multiset <int> lo, hi;
    
    void balance() {
        while (sz(lo) > sz(hi)) {
            int x = *lo.rbegin();
            hi.emplace(x);
            suml -= x;
            sumr += x;
            lo.erase(lo.find(x));
        }
    
        while (sz(hi) > sz(lo)) {
            int x = *hi.begin();
            lo.emplace(x);
            suml += x;
            sumr -= x;
            hi.erase(hi.find(x));
        }
    }
    
    void add(int x) {
        lo.emplace(x);
        suml += x;
    
        balance();
    }
    
    void solve() {
        sort(all(opposite), [&](pair <int, int> a, pair <int, int> b) -> bool {
            return a.first + a.second < b.first + b.second;
        });

        vector <int> pref(sz(opposite) + 1);

        for (int i = 0; i < sz(opposite); ++i) {
            add(opposite[i].first);
            add(opposite[i].second);

            pref[i + 1] = sumr - suml;
        }

        int ans = pref[sz(opposite)];
        for (int i = sz(opposite) - 1; i >= 0; --i) {
            add(opposite[i].first);
            add(opposite[i].second);

            minimize(ans, pref[i] + sumr - suml);
        }
    
        cout << ans + same_side << '\n';
    }
}

void solve() {
    cin >> k >> n;

    for (int i = 1; i <= n; ++i) {
        char p, q; int s, t; cin >> p >> s >> q >> t;

        if (p == q)
            same_side += abs(s - t);
        else
            buildings.push_back(s), buildings.push_back(t), 
            opposite.emplace_back(min(s, t), max(s, t));
    }

    sort(all(buildings));

    if (k == 1)
        sub12 :: solve();
    else {
        if (n <= 100)
            sub3 :: solve();
        // else if (n <= 1000)
        //     sub4 :: solve();
        else
            sub5 :: solve();
    }
}

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct

Subtask #2
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 756 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 416 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 16 ms 3776 KB Output is correct
13 Correct 33 ms 3780 KB Output is correct
14 Correct 24 ms 3780 KB Output is correct
15 Correct 19 ms 2504 KB Output is correct
16 Correct 19 ms 3824 KB Output is correct
17 Correct 23 ms 3816 KB Output is correct
18 Correct 26 ms 3776 KB Output is correct
19 Correct 30 ms 3832 KB Output is correct
20 Correct 21 ms 3608 KB Output is correct
21 Correct 28 ms 3776 KB Output is correct

Subtask #3
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 3 ms 348 KB Output is correct
4 Correct 4 ms 348 KB Output is correct
5 Correct 1 ms 388 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 5 ms 348 KB Output is correct
8 Correct 5 ms 464 KB Output is correct
9 Correct 5 ms 344 KB Output is correct
10 Correct 5 ms 544 KB Output is correct
11 Correct 5 ms 348 KB Output is correct
12 Correct 5 ms 348 KB Output is correct

Subtask #4
0 / 32.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 3 ms 348 KB Output is correct
4 Correct 4 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 5 ms 348 KB Output is correct
8 Correct 5 ms 348 KB Output is correct
9 Correct 5 ms 456 KB Output is correct
10 Correct 5 ms 344 KB Output is correct
11 Correct 5 ms 348 KB Output is correct
12 Correct 7 ms 604 KB Output is correct
13 Incorrect 2 ms 600 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #5
0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 3 ms 348 KB Output is correct
4 Correct 3 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 5 ms 344 KB Output is correct
8 Correct 5 ms 348 KB Output is correct
9 Correct 6 ms 348 KB Output is correct
10 Correct 5 ms 348 KB Output is correct
11 Correct 5 ms 348 KB Output is correct
12 Correct 5 ms 348 KB Output is correct
13 Incorrect 1 ms 604 KB Output isn't correct
14 Halted 0 ms 0 KB -