oj.uz

Submission #806721

# Submission time Handle Problem Language Result Execution time Memory
806721 2023-08-04T09:11:40 Z ashcomp LOSTIKS (INOI20_lostiks) C++17
23 / 100
 2000 ms 368788 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 = 2e6 + 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][22] , ps_rmq[maxn<<1][22] , rrmq[maxn<<1][22] , ps_rrmq[maxn<<1][22] , 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;
        
}
inline 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
inline 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];
        }
}
inline 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

# Verdict Execution time Memory Grader output
1 Correct 75 ms 188160 KB Output is correct
2 Correct 75 ms 188236 KB Output is correct
3 Correct 207 ms 269048 KB Output is correct
4 Correct 205 ms 268948 KB Output is correct
5 Correct 211 ms 269228 KB Output is correct
6 Correct 204 ms 268988 KB Output is correct
7 Correct 216 ms 269100 KB Output is correct
8 Correct 214 ms 269248 KB Output is correct
9 Correct 214 ms 269488 KB Output is correct
10 Correct 217 ms 269112 KB Output is correct
11 Correct 209 ms 269096 KB Output is correct
12 Correct 205 ms 271620 KB Output is correct
13 Correct 210 ms 271048 KB Output is correct
14 Correct 202 ms 270368 KB Output is correct
15 Correct 203 ms 271912 KB Output is correct
16 Correct 228 ms 273004 KB Output is correct
17 Correct 210 ms 273040 KB Output is correct
18 Correct 216 ms 273904 KB Output is correct
19 Correct 208 ms 280380 KB Output is correct
20 Correct 209 ms 280040 KB Output is correct
21 Correct 209 ms 279780 KB Output is correct
22 Correct 88 ms 188408 KB Output is correct
23 Correct 76 ms 188468 KB Output is correct
24 Correct 76 ms 188332 KB Output is correct
25 Correct 85 ms 188424 KB Output is correct
26 Correct 77 ms 188360 KB Output is correct

Subtask #2
0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 76 ms 188176 KB Output is correct
2 Correct 82 ms 188284 KB Output is correct
3 Correct 77 ms 188620 KB Output is correct
4 Correct 75 ms 188556 KB Output is correct
5 Correct 575 ms 284344 KB Output is correct
6 Correct 476 ms 284268 KB Output is correct
7 Correct 736 ms 284268 KB Output is correct
8 Correct 475 ms 284272 KB Output is correct
9 Correct 593 ms 284404 KB Output is correct
10 Correct 271 ms 284304 KB Output is correct
11 Correct 277 ms 284316 KB Output is correct
12 Correct 282 ms 284304 KB Output is correct
13 Correct 275 ms 284196 KB Output is correct
14 Correct 280 ms 284400 KB Output is correct
15 Correct 600 ms 284300 KB Output is correct
16 Correct 713 ms 284276 KB Output is correct
17 Correct 562 ms 284288 KB Output is correct
18 Correct 279 ms 284492 KB Output is correct
19 Correct 271 ms 284492 KB Output is correct
20 Correct 281 ms 284580 KB Output is correct
21 Correct 267 ms 284612 KB Output is correct
22 Correct 268 ms 285076 KB Output is correct
23 Correct 295 ms 285064 KB Output is correct
24 Correct 274 ms 285048 KB Output is correct
25 Execution timed out 2089 ms 368788 KB Time limit exceeded
26 Halted 0 ms 0 KB -

Subtask #3
0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 75 ms 188160 KB Output is correct
2 Correct 75 ms 188236 KB Output is correct
3 Correct 207 ms 269048 KB Output is correct
4 Correct 205 ms 268948 KB Output is correct
5 Correct 211 ms 269228 KB Output is correct
6 Correct 204 ms 268988 KB Output is correct
7 Correct 216 ms 269100 KB Output is correct
8 Correct 214 ms 269248 KB Output is correct
9 Correct 214 ms 269488 KB Output is correct
10 Correct 217 ms 269112 KB Output is correct
11 Correct 209 ms 269096 KB Output is correct
12 Correct 205 ms 271620 KB Output is correct
13 Correct 210 ms 271048 KB Output is correct
14 Correct 202 ms 270368 KB Output is correct
15 Correct 203 ms 271912 KB Output is correct
16 Correct 228 ms 273004 KB Output is correct
17 Correct 210 ms 273040 KB Output is correct
18 Correct 216 ms 273904 KB Output is correct
19 Correct 208 ms 280380 KB Output is correct
20 Correct 209 ms 280040 KB Output is correct
21 Correct 209 ms 279780 KB Output is correct
22 Correct 88 ms 188408 KB Output is correct
23 Correct 76 ms 188468 KB Output is correct
24 Correct 76 ms 188332 KB Output is correct
25 Correct 85 ms 188424 KB Output is correct
26 Correct 77 ms 188360 KB Output is correct
27 Correct 76 ms 188176 KB Output is correct
28 Correct 82 ms 188284 KB Output is correct
29 Correct 77 ms 188620 KB Output is correct
30 Correct 75 ms 188556 KB Output is correct
31 Correct 575 ms 284344 KB Output is correct
32 Correct 476 ms 284268 KB Output is correct
33 Correct 736 ms 284268 KB Output is correct
34 Correct 475 ms 284272 KB Output is correct
35 Correct 593 ms 284404 KB Output is correct
36 Correct 271 ms 284304 KB Output is correct
37 Correct 277 ms 284316 KB Output is correct
38 Correct 282 ms 284304 KB Output is correct
39 Correct 275 ms 284196 KB Output is correct
40 Correct 280 ms 284400 KB Output is correct
41 Correct 600 ms 284300 KB Output is correct
42 Correct 713 ms 284276 KB Output is correct
43 Correct 562 ms 284288 KB Output is correct
44 Correct 279 ms 284492 KB Output is correct
45 Correct 271 ms 284492 KB Output is correct
46 Correct 281 ms 284580 KB Output is correct
47 Correct 267 ms 284612 KB Output is correct
48 Correct 268 ms 285076 KB Output is correct
49 Correct 295 ms 285064 KB Output is correct
50 Correct 274 ms 285048 KB Output is correct
51 Execution timed out 2089 ms 368788 KB Time limit exceeded
52 Halted 0 ms 0 KB -