Submission #613817

#	Time	Username	Problem	Language	Result	Execution time	Memory
613817		AugustinasJucas	Road Closures (APIO21_roads)	C++14	36 / 100	514 ms	68604 KiB

roads

#include "roads.h"

#include <bits/stdc++.h>
using namespace std;
const int dydis = 1e5  + 10;
vector<pair<int, int> > gr[dydis];
const long long inf = 1e14 + 1;
int n, m;
vector<int> mas;

auto lin() {
 /// Galiu praleisti max 1 is eiles. Kokia min suma?
    long long dp[n]; /// dp[i] - turiu visus iki i ir i-aji emiau. Kokia min suma?

    dp[0] = mas[0];
    dp[1] = mas[1];
    for(int i = 2; i < n; i++) {
        dp[i] = min(dp[i-1] + mas[i], dp[i-2] + mas[i]);
    }
    vector<long long> ret(n, 0);
    for(auto x : mas) ret[0] += x;
    ret[1] = min(dp[n-1], dp[n-2]);
    return ret;
}
auto starr() {
 //cout << "star - " << true << endl;
    sort(mas.begin(), mas.end());
    reverse(mas.begin(), mas.end());
    vector<long long> ret(n, 0);
    for(auto x : mas) ret[0] += x;
    long long sum = 0;
    for(int i = n-1; i > 0; i--) {
        if(i != n- 1) sum += mas[i];
        ret[i] = sum;

    }
    return ret;
}

long long dp[2100][2100][2];    /// dp[v][k][isimuVirsu]
void dfs(int v, int came, int wUp, int k) {
    vector<long long> pos;
    for(auto x : gr[v]) {
        if(x.first == came) continue;
        dfs(x.first, v, x.second, k);
        pos.push_back(dp[x.first][k][1]);
    }
    sort(pos.begin(), pos.end());

    int reikIsimt = 0;

    if(k == 0) { /// turiu paimti viska!!!
        long long sm = wUp;
        for(auto x : gr[v]) {
            if(x.first == came) continue;
            sm += dp[x.first][k][1];
        }
        dp[v][k][1] = sm;
        dp[v][k][0] = inf;
        if(v == 0) dp[v][k][0] = sm;
        return ;
    }

    /// dp[v][k][0] - jei neimu virsaus
    reikIsimt = max(0, (int)gr[v].size() - k);
    long long sum = 0;
    vector<long long> vec;
    for(auto x : gr[v]) {
        if(x.first == came) continue;
        sum += dp[x.first][k][0];   /// pridedu kas bus jei neerasinsiu
        vec.push_back(-dp[x.first][k][0] + dp[x.first][k][1]);
    }
    sort(vec.begin(), vec.end());
    dp[v][k][0] = sum;
    for(int i = 0; i < reikIsimt; i++) {
        dp[v][k][0] += vec[i];
    }
    for(int i = reikIsimt; i < vec.size(); i++) if(vec[i] < 0) dp[v][k][0] += vec[i];


    dp[v][k][1] = sum + wUp;
    reikIsimt = max(0, (int)gr[v].size() - k - 1);
    for(int i = 0; i < reikIsimt; i++) {
        dp[v][k][1] += vec[i];
    }
    for(int i = reikIsimt; i < vec.size(); i++) if(vec[i] < 0) dp[v][k][1] += vec[i];

}

vector<long long> minimum_closure_costs(int N, std::vector<int> U,
                                             std::vector<int> V,
                                             std::vector<int> W) {
    n = N; m = W.size();
    bool line = true, star = true;

    for(int i = 0; i < m; i++) {
        int a = U[i]; int b = V[i]; int w = W[i];
        if(a != b-1) line = false;
        if(a != 0) star = false;
        gr[a].push_back({b, w});
        gr[b].push_back({a, w});
        mas.push_back(w);
    }

    if(line) {
        return lin();
    }
    if(star) {
        return starr();
    }
    vector<long long> ret(n, 0);
    for(int i = 0; i < n; i++) {
        dfs(0, 0, 0, i);
        ret[i] = dp[0][i][0];
    }

    return ret;
}

Compilation message (stderr)

roads.cpp: In function 'void dfs(int, int, int, int)':
roads.cpp:78:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |     for(int i = reikIsimt; i < vec.size(); i++) if(vec[i] < 0) dp[v][k][0] += vec[i];
      |                            ~~^~~~~~~~~~~~
roads.cpp:86:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   86 |     for(int i = reikIsimt; i < vec.size(); i++) if(vec[i] < 0) dp[v][k][1] += vec[i];
      |                            ~~^~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 14 / 14
• Subtask 4: 10 / 10
• Subtask 5: 0 / 17
• Subtask 6: 0 / 25
• Subtask 7: 0 / 22