oj.uz

답안 #806703

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
806703 2023-08-04T09:01:02 Z ashcomp LOSTIKS (INOI20_lostiks) C++14
23 / 100
 2000 ms 274892 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);
        }
        
        /**/
        pre_LCA();
        for(int i=1; i<=n; i++){
                p[i] = -1;
        }
        dfs(ST);
        for(int i=1; i<(1<<((int)EG.size()))+(1<<((int)EG.size())); i++){
                for(int j=0; j<((int)EG.size())+1; 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)) );
                        }
                }
        }
        /***********************************/
        ps = ((int)EG.size());
        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}});

        for(int i=(1<<ps); i<(1<<(ps+1)); i++){
                int j = ps;
                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<<ps); i<(1<<(ps+1)); i++){
                ans = min(ans , dp[i][ps]);
        }
        /*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 94344 KB Output is correct
3 Correct 210 ms 171980 KB Output is correct
4 Correct 177 ms 171884 KB Output is correct
5 Correct 167 ms 171992 KB Output is correct
6 Correct 177 ms 171864 KB Output is correct
7 Correct 178 ms 172096 KB Output is correct
8 Correct 174 ms 172096 KB Output is correct
9 Correct 168 ms 172364 KB Output is correct
10 Correct 182 ms 172044 KB Output is correct
11 Correct 170 ms 172040 KB Output is correct
12 Correct 160 ms 174588 KB Output is correct
13 Correct 161 ms 174012 KB Output is correct
14 Correct 164 ms 173324 KB Output is correct
15 Correct 165 ms 174888 KB Output is correct
16 Correct 161 ms 175932 KB Output is correct
17 Correct 164 ms 176060 KB Output is correct
18 Correct 170 ms 176928 KB Output is correct
19 Correct 166 ms 183296 KB Output is correct
20 Correct 163 ms 183064 KB Output is correct
21 Correct 165 ms 182640 KB Output is correct
22 Correct 43 ms 94432 KB Output is correct
23 Correct 40 ms 94516 KB Output is correct
24 Correct 45 ms 94596 KB Output is correct
25 Correct 39 ms 94548 KB Output is correct
26 Correct 40 ms 94412 KB Output is correct

Subtask #2
0 / 36.0

# 결과 실행 시간 메모리 Grader output
1 Correct 41 ms 94348 KB Output is correct
2 Correct 43 ms 94288 KB Output is correct
3 Correct 44 ms 94668 KB Output is correct
4 Correct 39 ms 94656 KB Output is correct
5 Correct 681 ms 190120 KB Output is correct
6 Correct 463 ms 190124 KB Output is correct
7 Correct 793 ms 190152 KB Output is correct
8 Correct 577 ms 190124 KB Output is correct
9 Correct 637 ms 190128 KB Output is correct
10 Correct 282 ms 190148 KB Output is correct
11 Correct 293 ms 190160 KB Output is correct
12 Correct 286 ms 190172 KB Output is correct
13 Correct 283 ms 190156 KB Output is correct
14 Correct 281 ms 190156 KB Output is correct
15 Correct 573 ms 190152 KB Output is correct
16 Correct 759 ms 190176 KB Output is correct
17 Correct 620 ms 190140 KB Output is correct
18 Correct 286 ms 190312 KB Output is correct
19 Correct 283 ms 190388 KB Output is correct
20 Correct 286 ms 190284 KB Output is correct
21 Correct 283 ms 190392 KB Output is correct
22 Correct 287 ms 190924 KB Output is correct
23 Correct 283 ms 190924 KB Output is correct
24 Correct 295 ms 191052 KB Output is correct
25 Execution timed out 2088 ms 274892 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 94344 KB Output is correct
3 Correct 210 ms 171980 KB Output is correct
4 Correct 177 ms 171884 KB Output is correct
5 Correct 167 ms 171992 KB Output is correct
6 Correct 177 ms 171864 KB Output is correct
7 Correct 178 ms 172096 KB Output is correct
8 Correct 174 ms 172096 KB Output is correct
9 Correct 168 ms 172364 KB Output is correct
10 Correct 182 ms 172044 KB Output is correct
11 Correct 170 ms 172040 KB Output is correct
12 Correct 160 ms 174588 KB Output is correct
13 Correct 161 ms 174012 KB Output is correct
14 Correct 164 ms 173324 KB Output is correct
15 Correct 165 ms 174888 KB Output is correct
16 Correct 161 ms 175932 KB Output is correct
17 Correct 164 ms 176060 KB Output is correct
18 Correct 170 ms 176928 KB Output is correct
19 Correct 166 ms 183296 KB Output is correct
20 Correct 163 ms 183064 KB Output is correct
21 Correct 165 ms 182640 KB Output is correct
22 Correct 43 ms 94432 KB Output is correct
23 Correct 40 ms 94516 KB Output is correct
24 Correct 45 ms 94596 KB Output is correct
25 Correct 39 ms 94548 KB Output is correct
26 Correct 40 ms 94412 KB Output is correct
27 Correct 41 ms 94348 KB Output is correct
28 Correct 43 ms 94288 KB Output is correct
29 Correct 44 ms 94668 KB Output is correct
30 Correct 39 ms 94656 KB Output is correct
31 Correct 681 ms 190120 KB Output is correct
32 Correct 463 ms 190124 KB Output is correct
33 Correct 793 ms 190152 KB Output is correct
34 Correct 577 ms 190124 KB Output is correct
35 Correct 637 ms 190128 KB Output is correct
36 Correct 282 ms 190148 KB Output is correct
37 Correct 293 ms 190160 KB Output is correct
38 Correct 286 ms 190172 KB Output is correct
39 Correct 283 ms 190156 KB Output is correct
40 Correct 281 ms 190156 KB Output is correct
41 Correct 573 ms 190152 KB Output is correct
42 Correct 759 ms 190176 KB Output is correct
43 Correct 620 ms 190140 KB Output is correct
44 Correct 286 ms 190312 KB Output is correct
45 Correct 283 ms 190388 KB Output is correct
46 Correct 286 ms 190284 KB Output is correct
47 Correct 283 ms 190392 KB Output is correct
48 Correct 287 ms 190924 KB Output is correct
49 Correct 283 ms 190924 KB Output is correct
50 Correct 295 ms 191052 KB Output is correct
51 Execution timed out 2088 ms 274892 KB Time limit exceeded
52 Halted 0 ms 0 KB -