oj.uz

Submission #537780

# Submission time Handle Problem Language Result Execution time Memory
537780 2022-03-15T13:42:33 Z Lobo Beads and wires (APIO14_beads) C++17
57 / 100
 360 ms 131072 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], mark[maxn][4][2];
vector<pair<int,int>> g[maxn];

/*
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(mark[u][p][f][id]) return dp[u][p][f][id];
    mark[u][p][f][id] = 1;

    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(0);
                dp[i][k][1].pb(0);
                mark[i][k][0].pb(0);
                mark[i][k][1].pb(0);
            }
        }
    }
 
 
    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:43:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |         if(id == g[u].size()) return dp[u][p][f][id] = -inf;
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:66:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |         if(id == g[u].size()) return dp[u][p][f][id] = -inf;
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:89:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |         if(id == g[u].size()) {
      |            ~~~^~~~~~~~~~~~~~
beads.cpp:110:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |         if(id == g[u].size()) {
      |            ~~~^~~~~~~~~~~~~~
beads.cpp: In function 'void solve()':
beads.cpp:166:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  166 |         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:157:9: note: 'rt' was declared here
  157 |     int rt;
      |         ^~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 80144 KB Output is correct
2 Correct 38 ms 80080 KB Output is correct
3 Correct 37 ms 80060 KB Output is correct
4 Correct 37 ms 80072 KB Output is correct
5 Correct 40 ms 80156 KB Output is correct
6 Correct 47 ms 80120 KB Output is correct
7 Correct 41 ms 80084 KB Output is correct
8 Correct 44 ms 80124 KB Output is correct
9 Correct 44 ms 80076 KB Output is correct
10 Correct 62 ms 80100 KB Output is correct
11 Correct 48 ms 80092 KB Output is correct
12 Correct 42 ms 80136 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 80144 KB Output is correct
2 Correct 38 ms 80080 KB Output is correct
3 Correct 37 ms 80060 KB Output is correct
4 Correct 37 ms 80072 KB Output is correct
5 Correct 40 ms 80156 KB Output is correct
6 Correct 47 ms 80120 KB Output is correct
7 Correct 41 ms 80084 KB Output is correct
8 Correct 44 ms 80124 KB Output is correct
9 Correct 44 ms 80076 KB Output is correct
10 Correct 62 ms 80100 KB Output is correct
11 Correct 48 ms 80092 KB Output is correct
12 Correct 42 ms 80136 KB Output is correct
13 Correct 45 ms 80120 KB Output is correct
14 Correct 48 ms 80208 KB Output is correct
15 Correct 48 ms 80148 KB Output is correct
16 Correct 47 ms 80188 KB Output is correct
17 Correct 45 ms 80236 KB Output is correct
18 Correct 51 ms 80264 KB Output is correct
19 Correct 55 ms 80304 KB Output is correct
20 Correct 54 ms 80252 KB Output is correct
21 Correct 54 ms 80268 KB Output is correct
22 Correct 47 ms 80284 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 80144 KB Output is correct
2 Correct 38 ms 80080 KB Output is correct
3 Correct 37 ms 80060 KB Output is correct
4 Correct 37 ms 80072 KB Output is correct
5 Correct 40 ms 80156 KB Output is correct
6 Correct 47 ms 80120 KB Output is correct
7 Correct 41 ms 80084 KB Output is correct
8 Correct 44 ms 80124 KB Output is correct
9 Correct 44 ms 80076 KB Output is correct
10 Correct 62 ms 80100 KB Output is correct
11 Correct 48 ms 80092 KB Output is correct
12 Correct 42 ms 80136 KB Output is correct
13 Correct 45 ms 80120 KB Output is correct
14 Correct 48 ms 80208 KB Output is correct
15 Correct 48 ms 80148 KB Output is correct
16 Correct 47 ms 80188 KB Output is correct
17 Correct 45 ms 80236 KB Output is correct
18 Correct 51 ms 80264 KB Output is correct
19 Correct 55 ms 80304 KB Output is correct
20 Correct 54 ms 80252 KB Output is correct
21 Correct 54 ms 80268 KB Output is correct
22 Correct 47 ms 80284 KB Output is correct
23 Correct 66 ms 83008 KB Output is correct
24 Correct 63 ms 83028 KB Output is correct
25 Correct 70 ms 83020 KB Output is correct
26 Correct 90 ms 85836 KB Output is correct
27 Correct 107 ms 85836 KB Output is correct
28 Correct 106 ms 87620 KB Output is correct
29 Correct 104 ms 87344 KB Output is correct
30 Correct 100 ms 87232 KB Output is correct
31 Correct 109 ms 86840 KB Output is correct

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 80144 KB Output is correct
2 Correct 38 ms 80080 KB Output is correct
3 Correct 37 ms 80060 KB Output is correct
4 Correct 37 ms 80072 KB Output is correct
5 Correct 40 ms 80156 KB Output is correct
6 Correct 47 ms 80120 KB Output is correct
7 Correct 41 ms 80084 KB Output is correct
8 Correct 44 ms 80124 KB Output is correct
9 Correct 44 ms 80076 KB Output is correct
10 Correct 62 ms 80100 KB Output is correct
11 Correct 48 ms 80092 KB Output is correct
12 Correct 42 ms 80136 KB Output is correct
13 Correct 45 ms 80120 KB Output is correct
14 Correct 48 ms 80208 KB Output is correct
15 Correct 48 ms 80148 KB Output is correct
16 Correct 47 ms 80188 KB Output is correct
17 Correct 45 ms 80236 KB Output is correct
18 Correct 51 ms 80264 KB Output is correct
19 Correct 55 ms 80304 KB Output is correct
20 Correct 54 ms 80252 KB Output is correct
21 Correct 54 ms 80268 KB Output is correct
22 Correct 47 ms 80284 KB Output is correct
23 Correct 66 ms 83008 KB Output is correct
24 Correct 63 ms 83028 KB Output is correct
25 Correct 70 ms 83020 KB Output is correct
26 Correct 90 ms 85836 KB Output is correct
27 Correct 107 ms 85836 KB Output is correct
28 Correct 106 ms 87620 KB Output is correct
29 Correct 104 ms 87344 KB Output is correct
30 Correct 100 ms 87232 KB Output is correct
31 Correct 109 ms 86840 KB Output is correct
32 Correct 352 ms 108864 KB Output is correct
33 Correct 360 ms 108800 KB Output is correct
34 Correct 278 ms 108856 KB Output is correct
35 Runtime error 328 ms 131072 KB Execution killed with signal 9
36 Halted 0 ms 0 KB -