oj.uz

답안 #995001

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
995001 2024-06-08T09:40:28 Z Requiem Designated Cities (JOI19_designated_cities) C++17
16 / 100
 161 ms 61272 KB 
#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define inf 1e18
#define fi first
#define se second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define endl '\n'
#define pi 3.14159265359
#define TASKNAME "designated"
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef pair<ii, ii> iiii;
typedef vector<int> vi;
const int MAXN = 5e5 + 9;

ii edge[MAXN];
vector<int> g[MAXN];
int n, q, E[MAXN];

int rev(int x){
    return ((x&1) ? (x + 1) : (x - 1));
}
namespace subtask2{
     bool check(){
          return (q == 1 and E[1] == 1);
     }

     int dp[MAXN];

     void dfs1(int u, int p){
          for(auto id: g[u]){
              int v = edge[id].se;
              if (v == p) continue;
              dfs1(v, u);
              int revid = rev(id);
              dp[u] += edge[revid].fi + dp[v];
          }
     }

     void transition(int u ,int v, int id){ //chuyen trang thai tu u sang v voi canh dang xet la id.
          dp[u] -= dp[v] + edge[rev(id)].fi;
          dp[v] += dp[u] + edge[id].fi;
     }

     int ans = 0;
     void dfs2(int u, int p){
          maximize(ans, dp[u]);

          for(auto id: g[u]){
              int v = edge[id].se;
              if (v == p) continue;

              transition(u, v, id);

              dfs2(v, u);

              transition(v, u, rev(id));
          }
     }
     void solve(){
          dfs1(1, -1);
          dfs2(1, -1);
          int sum = 0;
          for(int i = 1; i < 2 * n; i++){
              sum += edge[i].fi;
          }

          cout << sum - ans << endl;
     }
}

namespace subtask3{
    bool check(){
        return (q == 1 and E[1] == 2);
    }

    int dp[MAXN], maxdepth[MAXN], ans = 0;
    void dfs1(int u, int p){
         for(auto id: g[u]){
             int v = edge[id].se;
             if (v == p) continue;

             dfs1(v, u);

             dp[u] += edge[rev(id)].fi + dp[v];
             maximize(maxdepth[u], maxdepth[v] + edge[id].fi);
         }
    }

    void update(ii &a, int b){
        if (a.fi < b){
            a.se = a.fi;
            a.fi = b;
        }
        else if (a.se < b){
            a.se = b;
        }
    }

     void transition(int u ,int v, int id){ //chuyen trang thai tu u sang v voi canh dang xet la id.
          dp[u] -= dp[v] + edge[rev(id)].fi;
          dp[v] += dp[u] + edge[id].fi;
     }

    void dfs2(int u, int p, int mxd){
         ii pairs = {-inf, -inf};
         maximize(ans, dp[u] + max(mxd, maxdepth[u]));

         update(pairs, mxd);

//         cout << u << ' ' << mxd << ' ' << dp[u] << ' ' << ' ' << maxdepth[u] << ' ' << endl;
         for(auto id: g[u]){
             int v = edge[id].se;
             if (v == p) continue;
             update(pairs, maxdepth[v] + edge[id].fi);
         }

         for(auto id: g[u]){
             int v = edge[id].se;


             if (v == p) continue;

             transition(u, v, id);

             if (maxdepth[v] + edge[id].fi == pairs.fi){
                 dfs2(v, u, pairs.se + edge[rev(id)].fi);
             }
             else{
                 dfs2(v, u, pairs.fi + edge[rev(id)].fi);
             }

             transition(v, u, rev(id));
         }
    }
    void solve(){
        dfs1(1, -1);
        dfs2(1, -1, 0);

        int sum = 0;
        for(int i = 1; i < 2 * n; i++){
            sum += edge[i].fi;
        }
        cout << sum - ans << endl;
    }
}
main()
{
    fast;
    if (fopen(TASKNAME".inp","r")){
        freopen(TASKNAME".inp","r",stdin);
        freopen(TASKNAME".out","w",stdout);
    }

    cin >> n;
    for(int i = 0; i < n - 1; i++){
        int u, v, c, d;
        cin >> u >> v >> c >> d;
        edge[2 * i + 1] = {c, v};
        edge[2 * i + 2] = {d, u};

        g[u].pb(2 * i + 1);
        g[v].pb(2 * i + 2);
    }

    cin >> q;
    for(int i = 1; i <= q; i++){
        cin >> E[i];
    }

    if (subtask2::check()) return subtask2::solve(), 0;
    if (subtask3::check()) return subtask3::solve(), 0;
}
/**
Warning:
- MLE / TLE?
- Gioi han mang?
- Gia tri max phai luon gan cho -INF
- long long co can thiet khong?
- tran mang.
- code can than hon
- Nho sinh test de tranh RTE / TLE

--> Coi lai truoc khi nop
**/

Compilation message

designated_cities.cpp:155:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  155 | main()
      | ^~~~
designated_cities.cpp: In function 'int main()':
designated_cities.cpp:159:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  159 |         freopen(TASKNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
designated_cities.cpp:160:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  160 |         freopen(TASKNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 3 ms 16728 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 16728 KB Output is correct
2 Correct 146 ms 39648 KB Output is correct
3 Correct 123 ms 51276 KB Output is correct
4 Correct 92 ms 38352 KB Output is correct
5 Correct 126 ms 39628 KB Output is correct
6 Correct 108 ms 39760 KB Output is correct
7 Correct 84 ms 39872 KB Output is correct
8 Correct 115 ms 51456 KB Output is correct
9 Correct 75 ms 39924 KB Output is correct

Subtask #3
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 108 ms 41456 KB Output is correct
3 Correct 157 ms 61272 KB Output is correct
4 Correct 94 ms 38480 KB Output is correct
5 Correct 108 ms 41416 KB Output is correct
6 Correct 161 ms 42576 KB Output is correct
7 Correct 85 ms 41664 KB Output is correct
8 Correct 125 ms 52300 KB Output is correct
9 Correct 99 ms 40120 KB Output is correct

Subtask #4
0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 3 ms 16728 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 16728 KB Output is correct
2 Correct 146 ms 39648 KB Output is correct
3 Correct 123 ms 51276 KB Output is correct
4 Correct 92 ms 38352 KB Output is correct
5 Correct 126 ms 39628 KB Output is correct
6 Correct 108 ms 39760 KB Output is correct
7 Correct 84 ms 39872 KB Output is correct
8 Correct 115 ms 51456 KB Output is correct
9 Correct 75 ms 39924 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 108 ms 41456 KB Output is correct
12 Correct 157 ms 61272 KB Output is correct
13 Correct 94 ms 38480 KB Output is correct
14 Correct 108 ms 41416 KB Output is correct
15 Correct 161 ms 42576 KB Output is correct
16 Correct 85 ms 41664 KB Output is correct
17 Correct 125 ms 52300 KB Output is correct
18 Correct 99 ms 40120 KB Output is correct
19 Correct 3 ms 16732 KB Output is correct
20 Incorrect 83 ms 36464 KB Output isn't correct
21 Halted 0 ms 0 KB -

Subtask #6
0 / 44.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 3 ms 16728 KB Output isn't correct
2 Halted 0 ms 0 KB -