oj.uz

답안 #806687

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
806687 2023-08-04T08:50:54 Z ashcomp LOSTIKS (INOI20_lostiks) C++14
23 / 100
 2000 ms 274916 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<<22][22];
 
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 94284 KB Output is correct
2 Correct 40 ms 94352 KB Output is correct
3 Correct 171 ms 171908 KB Output is correct
4 Correct 167 ms 171864 KB Output is correct
5 Correct 202 ms 172012 KB Output is correct
6 Correct 181 ms 171976 KB Output is correct
7 Correct 191 ms 172092 KB Output is correct
8 Correct 171 ms 172072 KB Output is correct
9 Correct 176 ms 172408 KB Output is correct
10 Correct 170 ms 172092 KB Output is correct
11 Correct 184 ms 172132 KB Output is correct
12 Correct 173 ms 174540 KB Output is correct
13 Correct 169 ms 173996 KB Output is correct
14 Correct 171 ms 173332 KB Output is correct
15 Correct 163 ms 174832 KB Output is correct
16 Correct 172 ms 175944 KB Output is correct
17 Correct 168 ms 175972 KB Output is correct
18 Correct 178 ms 176776 KB Output is correct
19 Correct 169 ms 183320 KB Output is correct
20 Correct 172 ms 183044 KB Output is correct
21 Correct 170 ms 182652 KB Output is correct
22 Correct 40 ms 94488 KB Output is correct
23 Correct 40 ms 94412 KB Output is correct
24 Correct 40 ms 94448 KB Output is correct
25 Correct 42 ms 94540 KB Output is correct
26 Correct 42 ms 94488 KB Output is correct

Subtask #2
0 / 36.0

# 결과 실행 시간 메모리 Grader output
1 Correct 39 ms 94280 KB Output is correct
2 Correct 40 ms 94292 KB Output is correct
3 Correct 42 ms 94668 KB Output is correct
4 Correct 41 ms 94676 KB Output is correct
5 Correct 1275 ms 190124 KB Output is correct
6 Correct 915 ms 190124 KB Output is correct
7 Correct 1585 ms 190184 KB Output is correct
8 Correct 1000 ms 190132 KB Output is correct
9 Correct 1222 ms 190212 KB Output is correct
10 Correct 489 ms 190152 KB Output is correct
11 Correct 510 ms 190164 KB Output is correct
12 Correct 504 ms 190116 KB Output is correct
13 Correct 543 ms 190028 KB Output is correct
14 Correct 557 ms 190160 KB Output is correct
15 Correct 1077 ms 190152 KB Output is correct
16 Correct 1505 ms 190172 KB Output is correct
17 Correct 1134 ms 190144 KB Output is correct
18 Correct 527 ms 190392 KB Output is correct
19 Correct 502 ms 190412 KB Output is correct
20 Correct 542 ms 190392 KB Output is correct
21 Correct 503 ms 190472 KB Output is correct
22 Correct 492 ms 190928 KB Output is correct
23 Correct 525 ms 190916 KB Output is correct
24 Correct 487 ms 190940 KB Output is correct
25 Execution timed out 2067 ms 274916 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 94284 KB Output is correct
2 Correct 40 ms 94352 KB Output is correct
3 Correct 171 ms 171908 KB Output is correct
4 Correct 167 ms 171864 KB Output is correct
5 Correct 202 ms 172012 KB Output is correct
6 Correct 181 ms 171976 KB Output is correct
7 Correct 191 ms 172092 KB Output is correct
8 Correct 171 ms 172072 KB Output is correct
9 Correct 176 ms 172408 KB Output is correct
10 Correct 170 ms 172092 KB Output is correct
11 Correct 184 ms 172132 KB Output is correct
12 Correct 173 ms 174540 KB Output is correct
13 Correct 169 ms 173996 KB Output is correct
14 Correct 171 ms 173332 KB Output is correct
15 Correct 163 ms 174832 KB Output is correct
16 Correct 172 ms 175944 KB Output is correct
17 Correct 168 ms 175972 KB Output is correct
18 Correct 178 ms 176776 KB Output is correct
19 Correct 169 ms 183320 KB Output is correct
20 Correct 172 ms 183044 KB Output is correct
21 Correct 170 ms 182652 KB Output is correct
22 Correct 40 ms 94488 KB Output is correct
23 Correct 40 ms 94412 KB Output is correct
24 Correct 40 ms 94448 KB Output is correct
25 Correct 42 ms 94540 KB Output is correct
26 Correct 42 ms 94488 KB Output is correct
27 Correct 39 ms 94280 KB Output is correct
28 Correct 40 ms 94292 KB Output is correct
29 Correct 42 ms 94668 KB Output is correct
30 Correct 41 ms 94676 KB Output is correct
31 Correct 1275 ms 190124 KB Output is correct
32 Correct 915 ms 190124 KB Output is correct
33 Correct 1585 ms 190184 KB Output is correct
34 Correct 1000 ms 190132 KB Output is correct
35 Correct 1222 ms 190212 KB Output is correct
36 Correct 489 ms 190152 KB Output is correct
37 Correct 510 ms 190164 KB Output is correct
38 Correct 504 ms 190116 KB Output is correct
39 Correct 543 ms 190028 KB Output is correct
40 Correct 557 ms 190160 KB Output is correct
41 Correct 1077 ms 190152 KB Output is correct
42 Correct 1505 ms 190172 KB Output is correct
43 Correct 1134 ms 190144 KB Output is correct
44 Correct 527 ms 190392 KB Output is correct
45 Correct 502 ms 190412 KB Output is correct
46 Correct 542 ms 190392 KB Output is correct
47 Correct 503 ms 190472 KB Output is correct
48 Correct 492 ms 190928 KB Output is correct
49 Correct 525 ms 190916 KB Output is correct
50 Correct 487 ms 190940 KB Output is correct
51 Execution timed out 2067 ms 274916 KB Time limit exceeded
52 Halted 0 ms 0 KB -