oj.uz

답안 #1049122

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1049122 2024-08-08T13:39:24 Z beaconmc 경주 (Race) (IOI11_race) C++14
21 / 100
 3000 ms 96800 KB 
#include "race.h"
#include <bits/stdc++.h>
 
typedef long long ll;
#define FOR(i,x,y) for(ll i=x; i<y; i++)
#define FORNEG(i,x,y) for(ll i=x; i>y; i--)

using namespace std;

const ll maxn = 200005;
const ll INF = 1000000000;

vector<vector<ll>> edges[maxn];
ll par[maxn];
ll centpar[maxn];
ll depth[maxn];
ll realdepth[maxn];
ll ancc[maxn][20];
bool visited[maxn];
ll sub[maxn];

ll anc(ll a, ll x){
    if (a==0) return 0;
    if (x==0) return par[a];
    if (ancc[a][x] != -1) return ancc[a][x];
    return ancc[a][x] = anc(anc(a,x-1),x-1);
}

ll lca(ll a, ll b){
    if (depth[a] < depth[b]) swap(a,b);
    FORNEG(i,19,-1) if (depth[anc(a, i)] >= depth[b]) a = anc(a,i);
    if (a==b) return a;
    FORNEG(i,19,-1) if (anc(a,i) != anc(b,i)) a = anc(a,i), b = anc(b,i);
    return par[a];
}

void initdfs(ll a,ll p, ll d, ll dd){
    par[a] = p;
    depth[a] = d;
    realdepth[a] = dd;
    for (auto&i : edges[a]){
        if (i[0] != p) initdfs(i[0], a, d+1, dd+i[1]);
    }
}

ll centroid(ll root, ll a, ll p){
    for (auto&i : edges[a]){
        if (!visited[i[0]] && i[0] != p) return centroid(root, i[0], a);
    }
    return a;
}
void dfs(ll a, ll p){
    sub[a] = 1;
    for (auto&i : edges[a]) if(i[0] != p && !visited[i[0]]) dfs(i[0], a), sub[a] += sub[i[0]];
}
void build(ll a, ll p){
    dfs(a,p);
    ll cent = centroid(a, a, p);
    centpar[cent] = p;
    visited[cent] = 1;
    for (auto&i : edges[cent]){
        if (!visited[i[0]]) build(i[0], cent);
    }
}

map<ll, pair<array<ll,2>,array<ll,2>>> dists[maxn];

int best_path(int N, int K, int H[][2], int L[])
{
    FOR(i,0,maxn) par[i] = -1, centpar[i] = -1, par[i] -1, depth[i] = -1, realdepth[i] = -1,dists[i].clear();
    FOR(i,0,maxn)FOR(j,0,30) ancc[i][j] = -1;
    FOR(i,0,N){
        edges[H[i][0]].push_back({H[i][1], L[i]});
        edges[H[i][1]].push_back({H[i][0], L[i]});
    }
    initdfs(0,-1,0,0);
    build(0,-1);

    FOR(i,0,N){
        ll temp = centpar[i];
        ll prev = i;

        while (temp != -1){
            ll idk = lca(temp,i);
            ll cur = depth[temp] + depth[i] - depth[idk]*2;
           
            ll dist = realdepth[temp] + realdepth[i] - realdepth[idk]*2;

            if (dists[temp].count(dist) == 0) dists[temp][dist] = make_pair(array<ll,2>{cur, prev}, array<ll,2>{INF, INF});
            else{
                array<ll,2> a,b;
                a = dists[temp][dist].first;
                b = dists[temp][dist].second;

                if (a[1] == prev){
                    a[0] = min(a[0], cur);
                }else if (b[1] == prev){
                    b[0] = min(b[0], cur);
                }else{
                    if (cur <= a[0]) b = a, a = {cur, prev};
                    else if (cur <= b[0]) b = {cur, prev};
                }
                if (a[0] > b[0]) swap(a,b);
                dists[temp][dist] = make_pair(a,b);
            }
            prev = temp;
            temp = centpar[temp];

        }
    }
    ll ans = INF;
    FOR(i,0,N){
        for (auto&k : dists[i]){
            ll req = K-k.first;
            if (req == 0) ans = min(ans, k.second.first[0]);


            if (dists[i].count(req)==0) continue;
            if (req == k.first){

                ans = min(ans, k.second.first[0]+k.second.second[0]);
            }
            else{

                // cout << k.second.first[0] << " " << k.second.first[1] << endl;
                // cout << dists[i][req].first[0] << " " << dists[i][req].first[1] << endl;

                if (k.second.first[1] != dists[i][req].first[1]) ans = min(ans, k.second.first[0] + dists[i][req].first[0]);
                if (k.second.first[1] != dists[i][req].second[1]) ans = min(ans, k.second.first[0] + dists[i][req].second[0]);
                if (k.second.second[1] != dists[i][req].first[1]) ans = min(ans, k.second.second[0] + dists[i][req].first[0]);
                if (k.second.second[1] != dists[i][req].second[1]) ans = min(ans, k.second.second[0] + dists[i][req].second[0]);
            }
        }
    }

    if (ans >= INF) return -1;
    else return ans;

}

Compilation message

race.cpp: In function 'int best_path(int, int, int (*)[2], int*)':
race.cpp:70:56: warning: right operand of comma operator has no effect [-Wunused-value]
   70 |     FOR(i,0,maxn) par[i] = -1, centpar[i] = -1, par[i] -1, depth[i] = -1, realdepth[i] = -1,dists[i].clear();
      |                                                 ~~~~~~~^~
race.cpp:71:41: warning: iteration 20 invokes undefined behavior [-Waggressive-loop-optimizations]
   71 |     FOR(i,0,maxn)FOR(j,0,30) ancc[i][j] = -1;
      |                              ~~~~~~~~~~~^~~~
race.cpp:5:33: note: within this loop
    5 | #define FOR(i,x,y) for(ll i=x; i<y; i++)
......
   71 |     FOR(i,0,maxn)FOR(j,0,30) ancc[i][j] = -1;
      |                      ~~~~~~      
race.cpp:71:18: note: in expansion of macro 'FOR'
   71 |     FOR(i,0,maxn)FOR(j,0,30) ancc[i][j] = -1;
      |                  ^~~

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 57944 KB Output is correct
2 Correct 8 ms 57692 KB Output is correct
3 Correct 8 ms 57688 KB Output is correct
4 Correct 7 ms 57360 KB Output is correct
5 Correct 8 ms 57732 KB Output is correct
6 Correct 8 ms 57692 KB Output is correct
7 Correct 8 ms 57740 KB Output is correct
8 Correct 8 ms 57692 KB Output is correct
9 Correct 8 ms 57692 KB Output is correct
10 Correct 8 ms 57692 KB Output is correct
11 Correct 9 ms 57756 KB Output is correct
12 Correct 8 ms 57692 KB Output is correct
13 Correct 8 ms 57692 KB Output is correct
14 Correct 8 ms 57692 KB Output is correct
15 Correct 8 ms 57692 KB Output is correct
16 Correct 10 ms 57692 KB Output is correct
17 Correct 9 ms 57712 KB Output is correct
18 Correct 8 ms 57688 KB Output is correct

Subtask #2
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 57944 KB Output is correct
2 Correct 8 ms 57692 KB Output is correct
3 Correct 8 ms 57688 KB Output is correct
4 Correct 7 ms 57360 KB Output is correct
5 Correct 8 ms 57732 KB Output is correct
6 Correct 8 ms 57692 KB Output is correct
7 Correct 8 ms 57740 KB Output is correct
8 Correct 8 ms 57692 KB Output is correct
9 Correct 8 ms 57692 KB Output is correct
10 Correct 8 ms 57692 KB Output is correct
11 Correct 9 ms 57756 KB Output is correct
12 Correct 8 ms 57692 KB Output is correct
13 Correct 8 ms 57692 KB Output is correct
14 Correct 8 ms 57692 KB Output is correct
15 Correct 8 ms 57692 KB Output is correct
16 Correct 10 ms 57692 KB Output is correct
17 Correct 9 ms 57712 KB Output is correct
18 Correct 8 ms 57688 KB Output is correct
19 Correct 7 ms 57436 KB Output is correct
20 Correct 9 ms 57436 KB Output is correct
21 Correct 164 ms 76004 KB Output is correct
22 Correct 236 ms 96800 KB Output is correct
23 Correct 226 ms 96608 KB Output is correct
24 Correct 228 ms 96564 KB Output is correct
25 Correct 246 ms 96592 KB Output is correct
26 Correct 230 ms 96552 KB Output is correct
27 Correct 107 ms 58960 KB Output is correct
28 Correct 227 ms 96504 KB Output is correct
29 Correct 234 ms 96592 KB Output is correct
30 Correct 221 ms 96592 KB Output is correct
31 Correct 239 ms 96560 KB Output is correct
32 Correct 221 ms 96596 KB Output is correct
33 Correct 242 ms 96636 KB Output is correct
34 Correct 199 ms 90660 KB Output is correct
35 Correct 169 ms 88656 KB Output is correct
36 Correct 129 ms 84228 KB Output is correct
37 Correct 144 ms 84304 KB Output is correct
38 Correct 199 ms 90972 KB Output is correct

Subtask #3
0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 57944 KB Output is correct
2 Correct 8 ms 57692 KB Output is correct
3 Correct 8 ms 57688 KB Output is correct
4 Correct 7 ms 57360 KB Output is correct
5 Correct 8 ms 57732 KB Output is correct
6 Correct 8 ms 57692 KB Output is correct
7 Correct 8 ms 57740 KB Output is correct
8 Correct 8 ms 57692 KB Output is correct
9 Correct 8 ms 57692 KB Output is correct
10 Correct 8 ms 57692 KB Output is correct
11 Correct 9 ms 57756 KB Output is correct
12 Correct 8 ms 57692 KB Output is correct
13 Correct 8 ms 57692 KB Output is correct
14 Correct 8 ms 57692 KB Output is correct
15 Correct 8 ms 57692 KB Output is correct
16 Correct 10 ms 57692 KB Output is correct
17 Correct 9 ms 57712 KB Output is correct
18 Correct 8 ms 57688 KB Output is correct
19 Execution timed out 3031 ms 72528 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 57.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 57944 KB Output is correct
2 Correct 8 ms 57692 KB Output is correct
3 Correct 8 ms 57688 KB Output is correct
4 Correct 7 ms 57360 KB Output is correct
5 Correct 8 ms 57732 KB Output is correct
6 Correct 8 ms 57692 KB Output is correct
7 Correct 8 ms 57740 KB Output is correct
8 Correct 8 ms 57692 KB Output is correct
9 Correct 8 ms 57692 KB Output is correct
10 Correct 8 ms 57692 KB Output is correct
11 Correct 9 ms 57756 KB Output is correct
12 Correct 8 ms 57692 KB Output is correct
13 Correct 8 ms 57692 KB Output is correct
14 Correct 8 ms 57692 KB Output is correct
15 Correct 8 ms 57692 KB Output is correct
16 Correct 10 ms 57692 KB Output is correct
17 Correct 9 ms 57712 KB Output is correct
18 Correct 8 ms 57688 KB Output is correct
19 Correct 7 ms 57436 KB Output is correct
20 Correct 9 ms 57436 KB Output is correct
21 Correct 164 ms 76004 KB Output is correct
22 Correct 236 ms 96800 KB Output is correct
23 Correct 226 ms 96608 KB Output is correct
24 Correct 228 ms 96564 KB Output is correct
25 Correct 246 ms 96592 KB Output is correct
26 Correct 230 ms 96552 KB Output is correct
27 Correct 107 ms 58960 KB Output is correct
28 Correct 227 ms 96504 KB Output is correct
29 Correct 234 ms 96592 KB Output is correct
30 Correct 221 ms 96592 KB Output is correct
31 Correct 239 ms 96560 KB Output is correct
32 Correct 221 ms 96596 KB Output is correct
33 Correct 242 ms 96636 KB Output is correct
34 Correct 199 ms 90660 KB Output is correct
35 Correct 169 ms 88656 KB Output is correct
36 Correct 129 ms 84228 KB Output is correct
37 Correct 144 ms 84304 KB Output is correct
38 Correct 199 ms 90972 KB Output is correct
39 Execution timed out 3031 ms 72528 KB Time limit exceeded
40 Halted 0 ms 0 KB -