oj.uz

답안 #995003

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
995003 2024-06-08T09:57:52 Z Requiem Designated Cities (JOI19_designated_cities) C++17
16 / 100
 173 ms 55024 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;
    }
}

namespace subtask4{
    bool check(){
        return n <= 2000;
    }

    int dp[MAXN], par[MAXN], del[MAXN], answer[MAXN];
    ii maxdepth[MAXN];
    multiset<ii> st;


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

            dfs(v, u);
            par[v] = u;

            dp[u] += dp[v] + edge[rev(id)].fi;

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

    void deleteNode(int u){
        while(del[u] == 0){
            if (st.find(maxdepth[u]) != st.end()) st.erase(st.find(maxdepth[u]));
            del[u] = 1;
            u = par[u];

        }

    }
    void solve(){
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= n; j++){
                dp[j] = del[j] = 0;
            }
            dfs(i, -1);

            for(int j = 2; j <= n; j++){
                st.insert(maxdepth[j]);
            }
            maximize(answer[1], dp[i]);

            del[1] = true;
            int leave1 = maxdepth[1].se;
            dp[i] += maxdepth[1].fi;

            maximize(answer[2], dp[i]);

            for(int j = 3; j <= n; j++){
                if (st.size() == 0) {
                    maximize(answer[j], dp[i]);
                    continue;
                }
                ii it = *(--st.end());
                dp[i] += maxdepth[it.fi].fi;
                deleteNode(maxdepth[it.fi].se);
            }
        }

        int sum = 0;
        for(int i = 1; i < 2 * n; i++){
            sum += edge[i].fi;
        }

        for(int i = 1; i <= q; i++){
            cout << sum - answer[E[i]] << 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;

    if (subtask4::check()) return subtask4::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: In function 'void subtask4::solve()':
designated_cities.cpp:204:17: warning: unused variable 'leave1' [-Wunused-variable]
  204 |             int leave1 = maxdepth[1].se;
      |                 ^~~~~~
designated_cities.cpp: At global scope:
designated_cities.cpp:230:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  230 | main()
      | ^~~~
designated_cities.cpp: In function 'int main()':
designated_cities.cpp:234:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  234 |         freopen(TASKNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
designated_cities.cpp:235:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  235 |         freopen(TASKNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 22872 KB Output is correct
2 Runtime error 18 ms 46160 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 98 ms 31668 KB Output is correct
3 Correct 173 ms 43412 KB Output is correct
4 Correct 90 ms 31824 KB Output is correct
5 Correct 94 ms 31692 KB Output is correct
6 Correct 98 ms 33616 KB Output is correct
7 Correct 83 ms 31940 KB Output is correct
8 Correct 165 ms 43856 KB Output is correct
9 Correct 72 ms 32200 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 106 ms 33364 KB Output is correct
3 Correct 162 ms 55024 KB Output is correct
4 Correct 94 ms 33356 KB Output is correct
5 Correct 97 ms 35272 KB Output is correct
6 Correct 100 ms 38272 KB Output is correct
7 Correct 81 ms 33728 KB Output is correct
8 Correct 113 ms 44280 KB Output is correct
9 Correct 66 ms 32956 KB Output is correct

Subtask #4
0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 22872 KB Output is correct
2 Runtime error 18 ms 46160 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #5
0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 98 ms 31668 KB Output is correct
3 Correct 173 ms 43412 KB Output is correct
4 Correct 90 ms 31824 KB Output is correct
5 Correct 94 ms 31692 KB Output is correct
6 Correct 98 ms 33616 KB Output is correct
7 Correct 83 ms 31940 KB Output is correct
8 Correct 165 ms 43856 KB Output is correct
9 Correct 72 ms 32200 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 106 ms 33364 KB Output is correct
12 Correct 162 ms 55024 KB Output is correct
13 Correct 94 ms 33356 KB Output is correct
14 Correct 97 ms 35272 KB Output is correct
15 Correct 100 ms 38272 KB Output is correct
16 Correct 81 ms 33728 KB Output is correct
17 Correct 113 ms 44280 KB Output is correct
18 Correct 66 ms 32956 KB Output is correct
19 Correct 2 ms 16728 KB Output is correct
20 Incorrect 74 ms 30088 KB Output isn't correct
21 Halted 0 ms 0 KB -

Subtask #6
0 / 44.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 22872 KB Output is correct
2 Runtime error 18 ms 46160 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -