oj.uz

답안 #806686

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
806686 2023-08-04T08:49:42 Z ashcomp LOSTIKS (INOI20_lostiks) C++14
23 / 100
 2000 ms 266660 KB 
#include <bits/stdc++.h>
 
using namespace std;
 
#define all(x) x.begin() , x.end()
#define pii pair<int,int>
#define pll pair<ll,ll>
#define F first
#define S second
#define wall cerr<<"------------------------"<<endl
 
typedef long long ll;
 
const ll INF = 1e9;
const ll maxn = 1e6 + 10;
const ll mod = 1e9 + 7;
 
int n , m , k , ST , EN;
int h[maxn] , p[maxn] , st[maxn] , en[maxn];
int a[maxn<<1] , rmq[maxn<<1][21] , ps_rmq[maxn<<1][21] , rrmq[maxn<<1][21] , ps_rrmq[maxn<<1][21] , len[maxn<<1];
vector<int> g[maxn] , LSA;
bool mrk[maxn];
void DFS(int v)
{
        mrk[v] = 1;
        LSA.push_back(v);
        st[v] = LSA.size()-1;
        for(auto u : g[v]){
 
                if(mrk[u]==1)continue;
                p[u] = v;
                h[u] = h[v]+1;
                DFS(u);
                LSA.push_back(v);
        }
        en[v] = LSA.size()-1;
        
}
void pre_LCA()
{
        LSA.push_back(0);
        p[ST] = -1;
        h[ST] = 1;
        DFS(ST);
        m = LSA.size()-1;
        //wall;
        for(int i=1; i<=m; i++){
                a[i] = h[LSA[i]];
        }
        for(int j=0; j<21; j++){
                for(int i=1; i<=m; i++){
                        if(j==0){
                                rmq[i][j] = a[i];
                                rrmq[i][j] = a[i];
                                ps_rmq[i][j] = i;
                                ps_rrmq[i][j] = i;
                                continue;
                        }
                        if((i+(1<<j)-1)<=m){
                                rmq[i][j] = rmq[i][j-1];
                                ps_rmq[i][j] = ps_rmq[i][j-1];
                                if(rmq[i][j-1] > rmq[i+(1<<(j-1))][j-1]){
                                        rmq[i][j] = rmq[i+(1<<(j-1))][j-1];
                                        ps_rmq[i][j] = ps_rmq[i+(1<<(j-1))][j-1];
                                }
                        }
                        if((i-(1<<j)+1)>0){
                                rrmq[i][j] = rrmq[i][j-1];
                                ps_rrmq[i][j] = ps_rrmq[i][j-1];
                                if(rrmq[i][j-1] > rrmq[i-(1<<(j-1))][j-1]){
                                        rrmq[i][j] = rrmq[i-(1<<(j-1))][j-1];
                                        ps_rrmq[i][j] = ps_rrmq[i-(1<<(j-1))][j-1];
                                }
                        }
                }
        }
        int PS = 0;
        for(int i=1; i<=m; i++){
                if(((1<<PS)<<1)<=i){
                        PS++;
                }
                len[i] = PS;
        }
}//OK
int LCA(int v , int u)
{
        int l = min(st[v],st[u]) , r=max(st[v],st[u]);
        int ln = len[r-l+1];
        int x = rmq[l][ln] , y = rrmq[r][ln];
        if(x < y){
                int pos = ps_rmq[l][ln];
                return LSA[pos];
        }else{
                int pos = ps_rrmq[r][ln];
                return LSA[pos];
        }
}
int DIS(int v , int u)
{
        return (h[v]+h[u]-h[LCA(v,u)]-h[LCA(v,u)]);
}
 
vector<pii> eg[maxn];
bool mark[maxn];
int req[maxn];
map<int,int> MP[maxn]; 
void dfs(int v)
{
        mark[v] = 1;
        for(auto e : eg[v]){
                int u=e.F , w=e.S;
                if(mark[u]==1)continue;
                p[u] = v;
                req[u] = req[v];
                if(w!=0){
                        int x = MP[v][u];
                        req[u] |= (1<<x);
                }
                dfs(u);
        }
}
 
vector<pair<int,pii>> EG;
int dp[1<<21][21];
 
int main()
{
        ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
        cin>>n>>ST>>EN;
        int ps = 0;
        for(int i=1; i<n; i++){
                int v,u,w; cin>>v>>u>>w;
                if(w!=0){
                        MP[v][u] = ps;
                        MP[u][v] = ps;
                        ps++;
                        EG.push_back({w,{v,u}});
                }
                eg[v].push_back({u,w});
                eg[u].push_back({v,w});
                g[v].push_back(u);
                g[u].push_back(v);
        }
        eg[EN].push_back({n+1,EN});
        eg[n+1].push_back({EN,EN});
        MP[EN][n+1] = ps;
        MP[EN][n+1] = ps;
        EG.push_back({EN,{EN,n+1}});
        /**/
        pre_LCA();
        for(int i=1; i<=n; i++){
                p[i] = -1;
        }
        dfs(ST);
        for(int i=1; i<(1<<((int)EG.size())); i++){
                for(int j=0; j<((int)EG.size()); j++){
                        dp[i][j] = INF;
                }
        }
        for(int i=1; i<(1<<((int)EG.size())); i++){
                int pos = i;
                while(pos>0){
                        int j = __builtin_ctz(pos);
                        pos -= (1<<j);
                        int x = i^(1<<j);
                        int V=EG[j].S.F , U=EG[j].S.S , W=EG[j].F;
                        if(req[W]!=(req[W]&x))continue;
                        if(req[V]!=(req[V]&x) && req[U]!=(req[U]&x))continue;
                        if(x==0){
                                dp[i][j] = DIS(ST,W) + min(DIS(W,V),DIS(W,U));
                                continue;
                        }
                        int POS=i;
                        while(POS>0){
                                int f = __builtin_ctz(POS);
                                POS -= 1<<f;
                                int v=EG[f].S.F , u=EG[f].S.S;
                                int D1=DIS(ST,v) , D2=DIS(ST,u);
                                if(D1>D2){
                                        swap(v,u);
                                }
                                dp[i][j] = min(dp[i][j] , dp[x][f]+DIS(v,W)+min(DIS(W,V),DIS(W,U)) );
                        }
                }
        }
        int ans = INF;
        for(int i=1; i<(1<<((int)EG.size())); i++){
                int res = EG.size(); res--;
                ans = min(ans , dp[i][res]);
        }
        /*ll ans = INF;
        for(int i=1; i<(1<<((int)EG.size())); i++)
        {
                for(int j=0; j<((int)EG.size()); j++){
                        int V=EG[j].S.F , U=EG[j].S.S;
                        if(DIS(V,ST)>DIS(U,ST)){
                                swap(V,U);
                        }
                        if(req[EN]!=(req[EN]&i))continue;
                        ans = min(ans , (ll)dp[i][j] + DIS(V,EN));
                }
        }*/
        if(ans==INF){
                cout<<-1;
                return 0;
        }
        cout<<ans;
        return 0;
}
/*
3
1 3
1 2 3
1 3 2
*/
/*
10
1 10
1 2 0
2 3 0
3 4 0
4 5 2
2 6 4
2 7 0
7 8 5
8 9 6
9 10 0
ans = 15
*/
/**
4
1 4
1 2 0
1 3 2
3 4 1
ans = 4;
*/
/*
5
3 1
1 2 5
2 3 4
3 4 0
4 5 2
ans = 10;
*/

Subtask #1
23.0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 39 ms 94292 KB Output is correct
2 Correct 39 ms 94356 KB Output is correct
3 Correct 165 ms 171856 KB Output is correct
4 Correct 169 ms 171936 KB Output is correct
5 Correct 191 ms 171980 KB Output is correct
6 Correct 191 ms 171864 KB Output is correct
7 Correct 174 ms 172092 KB Output is correct
8 Correct 199 ms 172084 KB Output is correct
9 Correct 171 ms 172352 KB Output is correct
10 Correct 173 ms 172056 KB Output is correct
11 Correct 180 ms 172152 KB Output is correct
12 Correct 163 ms 174644 KB Output is correct
13 Correct 169 ms 174004 KB Output is correct
14 Correct 176 ms 173352 KB Output is correct
15 Correct 165 ms 174772 KB Output is correct
16 Correct 185 ms 175936 KB Output is correct
17 Correct 161 ms 176088 KB Output is correct
18 Correct 162 ms 176812 KB Output is correct
19 Correct 187 ms 183216 KB Output is correct
20 Correct 162 ms 183064 KB Output is correct
21 Correct 167 ms 182656 KB Output is correct
22 Correct 39 ms 94520 KB Output is correct
23 Correct 42 ms 94412 KB Output is correct
24 Correct 38 ms 94416 KB Output is correct
25 Correct 40 ms 94460 KB Output is correct
26 Correct 40 ms 94496 KB Output is correct

Subtask #2
0 / 36.0

# 결과 실행 시간 메모리 Grader output
1 Correct 38 ms 94292 KB Output is correct
2 Correct 39 ms 94248 KB Output is correct
3 Correct 45 ms 94660 KB Output is correct
4 Correct 41 ms 94672 KB Output is correct
5 Correct 1293 ms 186016 KB Output is correct
6 Correct 1010 ms 186020 KB Output is correct
7 Correct 1597 ms 186012 KB Output is correct
8 Correct 1002 ms 186144 KB Output is correct
9 Correct 1264 ms 186020 KB Output is correct
10 Correct 498 ms 186068 KB Output is correct
11 Correct 510 ms 186060 KB Output is correct
12 Correct 515 ms 186048 KB Output is correct
13 Correct 500 ms 186040 KB Output is correct
14 Correct 500 ms 186056 KB Output is correct
15 Correct 1060 ms 186044 KB Output is correct
16 Correct 1485 ms 186060 KB Output is correct
17 Correct 1122 ms 186032 KB Output is correct
18 Correct 553 ms 186280 KB Output is correct
19 Correct 510 ms 186272 KB Output is correct
20 Correct 515 ms 186288 KB Output is correct
21 Correct 487 ms 186356 KB Output is correct
22 Correct 489 ms 186812 KB Output is correct
23 Correct 560 ms 186808 KB Output is correct
24 Correct 499 ms 186836 KB Output is correct
25 Execution timed out 2081 ms 266660 KB Time limit exceeded
26 Halted 0 ms 0 KB -

Subtask #3
0 / 41.0

# 결과 실행 시간 메모리 Grader output
1 Correct 39 ms 94292 KB Output is correct
2 Correct 39 ms 94356 KB Output is correct
3 Correct 165 ms 171856 KB Output is correct
4 Correct 169 ms 171936 KB Output is correct
5 Correct 191 ms 171980 KB Output is correct
6 Correct 191 ms 171864 KB Output is correct
7 Correct 174 ms 172092 KB Output is correct
8 Correct 199 ms 172084 KB Output is correct
9 Correct 171 ms 172352 KB Output is correct
10 Correct 173 ms 172056 KB Output is correct
11 Correct 180 ms 172152 KB Output is correct
12 Correct 163 ms 174644 KB Output is correct
13 Correct 169 ms 174004 KB Output is correct
14 Correct 176 ms 173352 KB Output is correct
15 Correct 165 ms 174772 KB Output is correct
16 Correct 185 ms 175936 KB Output is correct
17 Correct 161 ms 176088 KB Output is correct
18 Correct 162 ms 176812 KB Output is correct
19 Correct 187 ms 183216 KB Output is correct
20 Correct 162 ms 183064 KB Output is correct
21 Correct 167 ms 182656 KB Output is correct
22 Correct 39 ms 94520 KB Output is correct
23 Correct 42 ms 94412 KB Output is correct
24 Correct 38 ms 94416 KB Output is correct
25 Correct 40 ms 94460 KB Output is correct
26 Correct 40 ms 94496 KB Output is correct
27 Correct 38 ms 94292 KB Output is correct
28 Correct 39 ms 94248 KB Output is correct
29 Correct 45 ms 94660 KB Output is correct
30 Correct 41 ms 94672 KB Output is correct
31 Correct 1293 ms 186016 KB Output is correct
32 Correct 1010 ms 186020 KB Output is correct
33 Correct 1597 ms 186012 KB Output is correct
34 Correct 1002 ms 186144 KB Output is correct
35 Correct 1264 ms 186020 KB Output is correct
36 Correct 498 ms 186068 KB Output is correct
37 Correct 510 ms 186060 KB Output is correct
38 Correct 515 ms 186048 KB Output is correct
39 Correct 500 ms 186040 KB Output is correct
40 Correct 500 ms 186056 KB Output is correct
41 Correct 1060 ms 186044 KB Output is correct
42 Correct 1485 ms 186060 KB Output is correct
43 Correct 1122 ms 186032 KB Output is correct
44 Correct 553 ms 186280 KB Output is correct
45 Correct 510 ms 186272 KB Output is correct
46 Correct 515 ms 186288 KB Output is correct
47 Correct 487 ms 186356 KB Output is correct
48 Correct 489 ms 186812 KB Output is correct
49 Correct 560 ms 186808 KB Output is correct
50 Correct 499 ms 186836 KB Output is correct
51 Execution timed out 2081 ms 266660 KB Time limit exceeded
52 Halted 0 ms 0 KB -