oj.uz

Submission #537789

# Submission time Handle Problem Language Result Execution time Memory
537789 2022-03-15T13:57:45 Z Lobo Beads and wires (APIO14_beads) C++17
57 / 100
 1000 ms 130040 KB 
#include<bits/stdc++.h>
using namespace std;
 
const int inf = (int) 1e9 + 10;
const int inf1 = (int) 1e9 + 10;
// #define int long long
#define dbl long double
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()


 
#define maxn 200020
 
int n;
vector<int> dp[maxn][4][2];
vector<pair<int,int>> g[maxn];

int MAX(int a, int b) {
    if(a > b) return a;
    return b;
}

/*
u = vertice
p = como esta
    0 = liga pro pai ou pra algum filho com azul e o outro azul que vai ligar para esse segundo
    3 = liga pro pai ou pra algum filho com azul e esse cara que vai ligar para o primeiro

    1 = liga pro pai com red ou nao pode mais ligar pra ninguem / ja fez sua ligacao
    2 = pode ligar para alguem com red ou para 2 com azul / ainda nao ligou pra ninguem

    
f = pode nao usar nada
    1 = tem que nao usar
    0 = tem que usar
*/

int sol(int u, int p, int f, int id, int ant) {
    if(dp[u][p][f][id] != -inf-1) return dp[u][p][f][id];
    dp[u][p][f][id] = 0;

    if(p == 0) {
        //tem que ligar para alguem com azul e nao se preocupa

        //se ja tiver passado por todo mundo é -inf
        if(id == g[u].size()) return dp[u][p][f][id] = -inf;
        int v = g[u][id].fr;
        int w = g[u][id].sc;
        if(v == ant) return dp[u][p][f][id] = sol(u,p,f,id+1,ant);

        int ans = -inf;

        //se o outro azul é v
        ans = MAX(ans, w + sol(v,2,0,0,u) + sol(u,1,f,id+1,ant));
        ans = MAX(ans, w + sol(v,2,f,0,u) + sol(u,1,0,id+1,ant));

        //só passa para o próximo podendo ligar para ele com azul 
        //(e o outro azul que vai estar ocupado) ou red
        ans = MAX(ans, MAX(sol(v,1,0,0,u),w+sol(v,3,0,0,u)) + sol(u,0,f,id+1,ant));
        ans = MAX(ans, MAX(sol(v,1,f,0,u),w+sol(v,3,f,0,u)) + sol(u,0,0,id+1,ant));

        // cout << u << " ja ligou azul p = 0 || f = " << f << " atual no " << v << " id " << id << " = " << " = " << ans << endl;
        return dp[u][p][f][id] = ans;
    }
    else if(p == 3) {
         //tem que ligar para alguem com azul e o filho azul nao pode ligar para mais ninguem

        //se ja tiver passado por todo mundo é -inf
        if(id == g[u].size()) return dp[u][p][f][id] = -inf;
        int v = g[u][id].fr;
        int w = g[u][id].sc;
        if(v == ant) return dp[u][p][f][id] = sol(u,p,f,id+1,ant);

        int ans = -inf;

        //se o outro azul é v
        ans = MAX(ans, w + sol(v,1,0,0,u) + sol(u,1,f,id+1,ant));
        ans = MAX(ans, w + sol(v,1,f,0,u) + sol(u,1,0,id+1,ant));

        //só passa para o próximo podendo ligar para ele com azul 
        //(e o outro azul que vai estar ocupado) ou red
        ans = MAX(ans, MAX(sol(v,1,0,0,u),w+sol(v,3,0,0,u)) + sol(u,3,f,id+1,ant));
        ans = MAX(ans, MAX(sol(v,1,f,0,u),w+sol(v,3,f,0,u)) + sol(u,3,0,id+1,ant));

        // cout << u << " ja ligou azul p = 3 || f = " << f << " atual no " << v << " id " << id << " = " << " = " << ans << endl;
        return dp[u][p][f][id] = ans;
    }
    else if(p == 1) {
        //ele ja fez a ligacao entao só pode passar pro próximo
        //o v pode ligar para ele com red ou azul

        if(id == g[u].size()) {
            if(f == 1) return dp[u][p][f][id] = -inf;
            else return dp[u][p][f][id] = 0;
        }
        int v = g[u][id].fr;
        int w = g[u][id].sc;
        if(v == ant) return dp[u][p][f][id] = sol(u,p,f,id+1,ant);

        int ans = -inf;

        //só passa para o próximo podendo ligar para ele com azul 
        //(e o outro azul que vai estar ocupado) ou red
        ans = MAX(ans, MAX(sol(v,1,0,0,u),w+sol(v,3,0,0,u)) + sol(u,1,f,id+1,ant));
        ans = MAX(ans, MAX(sol(v,1,f,0,u),w+sol(v,3,f,0,u)) + sol(u,1,0,id+1,ant));

        // cout << u << " ja ligou para todos || f = " << f << " atual no " << v << " = " << ans << endl;
        return dp[u][p][f][id] = ans;
    }
    else if(p == 2) {
        //ele nao ligou para ninguem ainda e se f = 1 pode continuear nao ligando

        if(id == g[u].size()) {
            if(f == 1) return dp[u][p][f][id] = 0; //ele fez a opcao de nao ligar para niguem
            else return dp[u][p][f][id] = -inf; //ele nao pode nao ligar para ninguem e mesmo assim fez
        }
        int v = g[u][id].fr;
        int w = g[u][id].sc;
        if(v == ant) return dp[u][p][f][id] = sol(u,p,f,id+1,ant);

        int ans = -inf;

        //só passa para o próximo podendo ligar para ele com azul 
        //(e o outro azul que vai estar ocupado) ou red
        ans = MAX(ans, MAX(sol(v,1,0,0,u),w+sol(v,3,0,0,u)) + sol(u,2,f,id+1,ant));
        ans = MAX(ans, MAX(sol(v,1,f,0,u),w+sol(v,3,f,0,u)) + sol(u,2,0,id+1,ant));

        //ele vai fazer o papel da aresta red que é quebrada pelo v
        ans = MAX(ans, w+sol(v,0,0,0,u) + sol(u,1,f,id+1,ant));
        ans = MAX(ans, w+sol(v,0,f,0,u) + sol(u,1,0,id+1,ant));

        //liga para o proximo com um uma aresta red
        ans = MAX(ans, sol(v,2,0,0,u) + sol(u,1,f,id+1,ant));
        ans = MAX(ans, sol(v,2,f,0,u) + sol(u,1,0,id+1,ant));

        //liga para o proximo com uma aresta azul e v que vai fazer a aresta red
        ans = MAX(ans, w+sol(v,1,0,0,u) + sol(u,0,f,id+1,ant));
        ans = MAX(ans, w+sol(v,1,f,0,u) + sol(u,0,0,id+1,ant));

        //liga para o proximo com uma aresta azul e o outro que vai fazer a aresta red
        ans = MAX(ans, w+sol(v,2,0,0,u) + sol(u,3,f,id+1,ant));
        ans = MAX(ans, w+sol(v,2,f,0,u) + sol(u,3,0,id+1,ant));

        // cout << u << " nao liga pra ninguem e || f = " << f << " atual no " << v << " = " << ans << endl;
        return dp[u][p][f][id] = ans;
    }
    return 0;
}
 
void solve() {
    cin >> n;
 
    for(int i = 1; i < n; i++) {
        int u,v,w;
        cin >> u >> v >> w;
        g[u].pb(mp(v,w));
        g[v].pb(mp(u,w));
    }
 
    int rt;
    for(int i = 1; i <= n; i++) {
        if(g[i].size() == 1) {
            rt = i;
            // break;
        }
    }

    for(int i = 1; i <= n; i++) {
        for(int j = 0; j <= g[i].size(); j++) {
            for(int k = 0; k <= 3; k++) {
                dp[i][k][0].pb(-inf-1);
                dp[i][k][1].pb(-inf-1);
            }
        }
    }
 
 
    cout << sol(rt,2,1,0,0) << endl;
}

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(0);
 
    // freopen("in.in", "r", stdin);
    // freopen("out.out", "w", stdout);
 
    int tt = 1;
    // cin >> tt;
    while(tt--) solve();
 
}

Compilation message

beads.cpp: In function 'int sol(int, int, int, int, int)':
beads.cpp:51:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |         if(id == g[u].size()) return dp[u][p][f][id] = -inf;
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:74:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |         if(id == g[u].size()) return dp[u][p][f][id] = -inf;
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:97:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |         if(id == g[u].size()) {
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:118:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |         if(id == g[u].size()) {
      |            ~~~^~~~~~~~~~~~~~
beads.cpp: In function 'void solve()':
beads.cpp:174:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  174 |         for(int j = 0; j <= g[i].size(); j++) {
      |                        ~~^~~~~~~~~~~~~~
beads.cpp:8:14: warning: 'rt' may be used uninitialized in this function [-Wmaybe-uninitialized]
    8 | #define endl '\n'
      |              ^~~~
beads.cpp:165:9: note: 'rt' was declared here
  165 |     int rt;
      |         ^~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 42580 KB Output is correct
2 Correct 22 ms 42524 KB Output is correct
3 Correct 22 ms 42496 KB Output is correct
4 Correct 21 ms 42580 KB Output is correct
5 Correct 21 ms 42568 KB Output is correct
6 Correct 23 ms 42588 KB Output is correct
7 Correct 21 ms 42592 KB Output is correct
8 Correct 23 ms 42560 KB Output is correct
9 Correct 25 ms 42612 KB Output is correct
10 Correct 21 ms 42580 KB Output is correct
11 Correct 22 ms 42596 KB Output is correct
12 Correct 27 ms 42556 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 42580 KB Output is correct
2 Correct 22 ms 42524 KB Output is correct
3 Correct 22 ms 42496 KB Output is correct
4 Correct 21 ms 42580 KB Output is correct
5 Correct 21 ms 42568 KB Output is correct
6 Correct 23 ms 42588 KB Output is correct
7 Correct 21 ms 42592 KB Output is correct
8 Correct 23 ms 42560 KB Output is correct
9 Correct 25 ms 42612 KB Output is correct
10 Correct 21 ms 42580 KB Output is correct
11 Correct 22 ms 42596 KB Output is correct
12 Correct 27 ms 42556 KB Output is correct
13 Correct 29 ms 42540 KB Output is correct
14 Correct 29 ms 42628 KB Output is correct
15 Correct 26 ms 42624 KB Output is correct
16 Correct 26 ms 42580 KB Output is correct
17 Correct 27 ms 42540 KB Output is correct
18 Correct 25 ms 42648 KB Output is correct
19 Correct 24 ms 42684 KB Output is correct
20 Correct 27 ms 42676 KB Output is correct
21 Correct 25 ms 42664 KB Output is correct
22 Correct 27 ms 42572 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 42580 KB Output is correct
2 Correct 22 ms 42524 KB Output is correct
3 Correct 22 ms 42496 KB Output is correct
4 Correct 21 ms 42580 KB Output is correct
5 Correct 21 ms 42568 KB Output is correct
6 Correct 23 ms 42588 KB Output is correct
7 Correct 21 ms 42592 KB Output is correct
8 Correct 23 ms 42560 KB Output is correct
9 Correct 25 ms 42612 KB Output is correct
10 Correct 21 ms 42580 KB Output is correct
11 Correct 22 ms 42596 KB Output is correct
12 Correct 27 ms 42556 KB Output is correct
13 Correct 29 ms 42540 KB Output is correct
14 Correct 29 ms 42628 KB Output is correct
15 Correct 26 ms 42624 KB Output is correct
16 Correct 26 ms 42580 KB Output is correct
17 Correct 27 ms 42540 KB Output is correct
18 Correct 25 ms 42648 KB Output is correct
19 Correct 24 ms 42684 KB Output is correct
20 Correct 27 ms 42676 KB Output is correct
21 Correct 25 ms 42664 KB Output is correct
22 Correct 27 ms 42572 KB Output is correct
23 Correct 46 ms 44116 KB Output is correct
24 Correct 46 ms 44108 KB Output is correct
25 Correct 48 ms 44132 KB Output is correct
26 Correct 55 ms 45640 KB Output is correct
27 Correct 64 ms 45616 KB Output is correct
28 Correct 75 ms 46956 KB Output is correct
29 Correct 65 ms 46840 KB Output is correct
30 Correct 64 ms 46604 KB Output is correct
31 Correct 54 ms 46496 KB Output is correct

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 42580 KB Output is correct
2 Correct 22 ms 42524 KB Output is correct
3 Correct 22 ms 42496 KB Output is correct
4 Correct 21 ms 42580 KB Output is correct
5 Correct 21 ms 42568 KB Output is correct
6 Correct 23 ms 42588 KB Output is correct
7 Correct 21 ms 42592 KB Output is correct
8 Correct 23 ms 42560 KB Output is correct
9 Correct 25 ms 42612 KB Output is correct
10 Correct 21 ms 42580 KB Output is correct
11 Correct 22 ms 42596 KB Output is correct
12 Correct 27 ms 42556 KB Output is correct
13 Correct 29 ms 42540 KB Output is correct
14 Correct 29 ms 42628 KB Output is correct
15 Correct 26 ms 42624 KB Output is correct
16 Correct 26 ms 42580 KB Output is correct
17 Correct 27 ms 42540 KB Output is correct
18 Correct 25 ms 42648 KB Output is correct
19 Correct 24 ms 42684 KB Output is correct
20 Correct 27 ms 42676 KB Output is correct
21 Correct 25 ms 42664 KB Output is correct
22 Correct 27 ms 42572 KB Output is correct
23 Correct 46 ms 44116 KB Output is correct
24 Correct 46 ms 44108 KB Output is correct
25 Correct 48 ms 44132 KB Output is correct
26 Correct 55 ms 45640 KB Output is correct
27 Correct 64 ms 45616 KB Output is correct
28 Correct 75 ms 46956 KB Output is correct
29 Correct 65 ms 46840 KB Output is correct
30 Correct 64 ms 46604 KB Output is correct
31 Correct 54 ms 46496 KB Output is correct
32 Correct 213 ms 57788 KB Output is correct
33 Correct 204 ms 57872 KB Output is correct
34 Correct 226 ms 57876 KB Output is correct
35 Correct 844 ms 103788 KB Output is correct
36 Correct 942 ms 103768 KB Output is correct
37 Correct 993 ms 103780 KB Output is correct
38 Execution timed out 1094 ms 130040 KB Time limit exceeded
39 Halted 0 ms 0 KB -