Submission #882666

#	Time	Username	Problem	Language	Result	Execution time	Memory
882666		vjudge1	Palembang Bridges (APIO15_bridge)	C++17	63 / 100	2029 ms	91620 KiB

bridge

/* Author : Mychecksdead  */
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
const int N = 1e6+100, M = 1e5+10, K = 52, MX = 30;



ll solv(vector<array<ll, 2>> &a){
  if(a.empty()) return 0ll;
  vector<pair<ll, ll>> v;

  for(int i = 0; i < a.size(); ++i) v.pb({a[i][0], 0}), v.pb({a[i][1], 1});


  vector<pair<ll, ll>> suf(v.size());
  vector<pair<ll, ll>> pref(v.size());

  sort(all(v));
  pref[0] = {0, 0};
  for(int i = 1; i < v.size(); ++i){
    pref[i] = pref[i - 1];
    if(v[i].second == 1) pref[i].first += v[i].first, pref[i].second++;
  }
  suf[v.size() - 1] = {0, 0};
  for(int i = v.size() - 2; i >= 0; --i){
    suf[i] = suf[i + 1];
    if(v[i].second == 0) suf[i].first += v[i].first, suf[i].second++;
  }
  ll best = 1e18;
  for(int i = 0; i < v.size(); ++i){
    if(abs(suf[i].second - pref[i].second) <= 1)
    best = min(best, suf[i].first - pref[i].first + (v[i].first * pref[i].second) - (v[i].first * suf[i].second));
  }
  return best*2 + a.size();
}

int k, n;
ll ans = 0;
pair<ll, ll> pref[N], suf[N], prefL[N], sufR[N];
array<ll, 2> a[N];
vector<int> L[N];
set<int> R[N];

void solve(){
  cin >> k >> n;
  int c = 0;
  for(int i = 1; i <= n; ++i){
    char c1, c2; ll x1, x2; cin >> c1 >> x1 >> c2 >> x2;
    if(c1 == c2){
      ans += abs(x1-x2);
    }else{
      ++c;
      a[c][0] = min(x1, x2);
      a[c][1] = max(x1, x2);
      ans += abs(x1-x2);
      // cout << a[c][0] << ' '<< a[c][1] << '\n';
    }
  }
  n = c;
  if(n==0){
    cout << ans;
    return;
  }
  sort(a+1, a+1+n);

  if(k == 1){
    vector<pair<ll, ll>> v;
    for(int i = 1; i <= n; ++i) v.pb({a[i][0], 0}), v.pb({a[i][1], 1});

    sort(all(v));
    pref[0] = {0, 0};
    for(int i = 1; i < v.size(); ++i){
      pref[i] = pref[i - 1];
      if(v[i].second == 1) pref[i].first += v[i].first, pref[i].second++;
    }

    suf[v.size() - 1] = {0, 0};
    for(int i = v.size() - 2; i >= 0; --i){
      suf[i] = suf[i + 1];
      if(v[i].second == 0) suf[i].first += v[i].first, suf[i].second++;
    }
    ll best = 1e18;
    for(int i = 0; i < v.size(); ++i){
      if(abs(suf[i].second - pref[i].second) <= 1)
      best = min(best, suf[i].first - pref[i].first + (v[i].first * pref[i].second) - (v[i].first * suf[i].second));
    }
    cout << ans + best*2 + n; 
  }else{
    ll best = 1e18;
    sort(a+1, a+1+n, [&](const array<ll, 2> &x, const array<ll, 2> &y){
      return x[0] + x[1] < y[0] + y[1];
    });

    for(int i = 0; i <= n; ++i){
      vector<array<ll, 2>> A, B;
      for(int j = 1; j <= i; ++j) A.pb(a[j]);
      for(int j = i+1; j <= n; ++j) B.pb(a[j]);
      best = min(best, solv(A) + solv(B));
    }


    cout << ans + best;
  }

}



int main(){
  cin.tie(0); ios::sync_with_stdio(0);
  int tt = 1, aa;
  // freopen("in.txt", "r", stdin);
  // freopen("out.txt", "w", stdout);
  while(tt--){
    solve();
    en;
  }
  cerr<<"time taken : "<<(float)clock()/CLOCKS_PER_SEC<<" seconds\n";
  return 0;
} 

Compilation message (stderr)

bridge.cpp: In function 'long long int solv(std::vector<std::array<long long int, 2> >&)':
bridge.cpp:18:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<long long int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |   for(int i = 0; i < a.size(); ++i) v.pb({a[i][0], 0}), v.pb({a[i][1], 1});
      |                  ~~^~~~~~~~~~
bridge.cpp:26:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |   for(int i = 1; i < v.size(); ++i){
      |                  ~~^~~~~~~~~~
bridge.cpp:36:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |   for(int i = 0; i < v.size(); ++i){
      |                  ~~^~~~~~~~~~
bridge.cpp: In function 'void solve()':
bridge.cpp:78:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |     for(int i = 1; i < v.size(); ++i){
      |                    ~~^~~~~~~~~~
bridge.cpp:89:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |     for(int i = 0; i < v.size(); ++i){
      |                    ~~^~~~~~~~~~
bridge.cpp: In function 'int main()':
bridge.cpp:117:15: warning: unused variable 'aa' [-Wunused-variable]
  117 |   int tt = 1, aa;
      |               ^~

• Subtask 1: 8 / 8
• Subtask 2: 14 / 14
• Subtask 3: 9 / 9
• Subtask 4: 32 / 32
• Subtask 5: 0 / 37