oj.uz

Submission #846753

# Submission time Handle Problem Language Result Execution time Memory
846753 2023-09-08T11:28:42 Z lohacho Railway Trip (JOI17_railway_trip) C++14
100 / 100
 219 ms 91712 KB 
#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
 
const int NS = (int)1e5 + 4, SZ = (int)3e5 + 4;
int a[NS + 4];
int seg[NS * 4 + 4];
int spa[SZ][17][4], dep[SZ], lcnt[SZ], pr[SZ][20];
int st[NS];
vector<int> pos[NS];
void build(int x, int s, int e){
    if(s == e){
        seg[x] = a[s];
        return;
    }
    int m = s + e >> 1;
    build(x * 2, s, m);
    build(x * 2 + 1, m + 1, e);
    seg[x] = max(seg[x * 2], seg[x * 2 + 1]);
}
 
int get(int x, int s, int e, int fs, int fe){
    if(fe < s || fs > e || fs > fe) return -1;
    if(fs <= s && fe >= e){
        return seg[x];
    }
    int m = s + e >> 1;
    return max(get(x * 2, s, m, fs, fe), get(x * 2 + 1, m + 1, e, fs, fe));
}
 
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int i, j;
 
    int n, k, q;
    cin >> n >> k >> q;
    a[0] = a[n + 1] = k + 1;
    for(i = 1; i <= n; ++i){
        cin >> a[i];
    }
    n += 2;
    build(1, 0, n - 1);
    for(i = 0; i < n; ++i){
        pos[a[i]].push_back(i);
    }
 
    int tn = 0;
    auto gen = [&](auto&&self, int x, int s, int e)->void{
        if(s + 1 >= e){
            st[s] = x;
            return;
        }
        int mx = get(1, 0, n - 1, s + 1, e - 1);
 
        vector<int> id;
        int now = s;
        while(true){
            now = lower_bound(pos[mx].begin(), pos[mx].end(), now + 1) - pos[mx].begin();
            if(now < (int)pos[mx].size() && pos[mx][now] < e){
                now = pos[mx][now];
                id.push_back(now);
            }
            else break;
        }
 
        for(int i = 0; i <= (int)id.size(); ++i){
            ++tn;
            dep[tn] = dep[x] + 1;
            lcnt[tn] = i;
            pr[tn][0] = x;
            spa[tn][0][0] = min(i, (int)id.size() - i + 2);
            spa[tn][0][1] = min(i + 1, (int)id.size() - i + 1);
            spa[tn][0][2] = min(i + 1, (int)id.size() - i + 1);
            spa[tn][0][3] = min(i + 2, (int)id.size() - i);
 
            self(self, tn, (i ? id[i - 1] : s), (i < (int)id.size() ? id[i] : e));
        }
    };
    gen(gen, 0, 0, n - 1);
 
    for(j = 1; j < 17; ++j){
        for(i = 0; i <= tn; ++i){
            pr[i][j] = pr[pr[i][j - 1]][j - 1];
            spa[i][j][0] = min(spa[i][j - 1][0] + spa[pr[i][j - 1]][j - 1][0], spa[i][j - 1][1] + spa[pr[i][j - 1]][j - 1][2]);
            spa[i][j][1] = min(spa[i][j - 1][0] + spa[pr[i][j - 1]][j - 1][1], spa[i][j - 1][1] + spa[pr[i][j - 1]][j - 1][3]);
            spa[i][j][2] = min(spa[i][j - 1][2] + spa[pr[i][j - 1]][j - 1][0], spa[i][j - 1][3] + spa[pr[i][j - 1]][j - 1][2]);
            spa[i][j][3] = min(spa[i][j - 1][2] + spa[pr[i][j - 1]][j - 1][1], spa[i][j - 1][3] + spa[pr[i][j - 1]][j - 1][3]);
        }
    }
 
    while(q--){
        int x, y;
        cin >> x >> y;
        x = st[x], y = st[y];
        
        if(dep[x] > dep[y]){
            swap(x, y);
        }

        int vxf = 0, vxs = 1;
        int vyf = 0, vys = 1;
        for(i = 16; i >= 0; --i){
            if(dep[y] - (1 << i) >= dep[x]){
                int nvyf = min(vyf + spa[y][i][0], vys + spa[y][i][2]), nvys = min(vyf + spa[y][i][1], vys + spa[y][i][3]);
                vyf = nvyf, vys = nvys;
                y = pr[y][i];
            }
        }
 
        for(i = 16; i >= 0; --i){
            if(pr[x][i] != pr[y][i]){
                int nvyf = min(vyf + spa[y][i][0], vys + spa[y][i][2]), nvys = min(vyf + spa[y][i][1], vys + spa[y][i][3]);
                vyf = nvyf, vys = nvys;
                y = pr[y][i];
                
                int nvxf = min(vxf + spa[x][i][0], vxs + spa[x][i][2]), nvxs = min(vxf + spa[x][i][1], vxs + spa[x][i][3]);
                vxf = nvxf, vxs = nvxs;
                x = pr[x][i];
            }
        }
 
        int ans;
        if(x == y) ans = min(vxf + vyf, vxs + vys);
        else{
            if(lcnt[x] < lcnt[y]) ans = vxs + vyf + lcnt[y] - lcnt[x] - 1;
            else ans = vxf + vys + lcnt[x] - lcnt[y] - 1;
            if(pr[x][0] > 0){
                ans = min(ans, vxf + spa[x][0][0] + vys + spa[y][0][3] + 1);
                ans = min(ans, vxs + spa[x][0][3] + vyf + spa[y][0][0] + 1);
            }
        }
 
        cout << ans - 1 << '\n';
    }
    
    return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 8796 KB Output is correct
2 Correct 1 ms 8796 KB Output is correct
3 Correct 2 ms 8796 KB Output is correct
4 Correct 1 ms 8796 KB Output is correct
5 Correct 2 ms 8792 KB Output is correct
6 Correct 1 ms 8796 KB Output is correct
7 Correct 2 ms 8796 KB Output is correct
8 Correct 1 ms 8796 KB Output is correct
9 Correct 1 ms 8852 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11096 KB Output is correct
2 Correct 71 ms 68720 KB Output is correct
3 Correct 86 ms 75324 KB Output is correct
4 Correct 83 ms 77100 KB Output is correct
5 Correct 78 ms 79196 KB Output is correct
6 Correct 82 ms 79184 KB Output is correct
7 Correct 96 ms 80468 KB Output is correct
8 Correct 38 ms 46172 KB Output is correct
9 Correct 59 ms 63244 KB Output is correct
10 Correct 52 ms 55128 KB Output is correct
11 Correct 64 ms 63308 KB Output is correct
12 Correct 65 ms 62812 KB Output is correct
13 Correct 64 ms 62812 KB Output is correct
14 Correct 69 ms 63316 KB Output is correct
15 Correct 63 ms 62804 KB Output is correct
16 Correct 68 ms 62800 KB Output is correct
17 Correct 88 ms 79184 KB Output is correct
18 Correct 88 ms 79184 KB Output is correct
19 Correct 85 ms 81724 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 131 ms 71248 KB Output is correct
2 Correct 129 ms 69204 KB Output is correct
3 Correct 125 ms 73400 KB Output is correct
4 Correct 129 ms 75272 KB Output is correct
5 Correct 133 ms 75348 KB Output is correct
6 Correct 133 ms 75344 KB Output is correct
7 Correct 140 ms 75528 KB Output is correct
8 Correct 93 ms 56572 KB Output is correct
9 Correct 77 ms 46448 KB Output is correct
10 Correct 86 ms 46220 KB Output is correct
11 Correct 78 ms 46364 KB Output is correct
12 Correct 79 ms 46284 KB Output is correct
13 Correct 81 ms 46280 KB Output is correct
14 Correct 75 ms 46448 KB Output is correct
15 Correct 79 ms 48352 KB Output is correct
16 Correct 106 ms 52644 KB Output is correct

Subtask #4
55.0 / 55.0

# Verdict Execution time Memory Grader output
1 Correct 145 ms 80868 KB Output is correct
2 Correct 173 ms 80784 KB Output is correct
3 Correct 134 ms 79700 KB Output is correct
4 Correct 142 ms 79952 KB Output is correct
5 Correct 75 ms 46376 KB Output is correct
6 Correct 127 ms 63784 KB Output is correct
7 Correct 132 ms 63688 KB Output is correct
8 Correct 112 ms 55800 KB Output is correct
9 Correct 125 ms 63572 KB Output is correct
10 Correct 126 ms 63532 KB Output is correct
11 Correct 126 ms 63108 KB Output is correct
12 Correct 137 ms 63568 KB Output is correct
13 Correct 135 ms 63292 KB Output is correct
14 Correct 172 ms 76292 KB Output is correct
15 Correct 178 ms 84256 KB Output is correct
16 Correct 219 ms 91712 KB Output is correct
17 Correct 163 ms 70708 KB Output is correct
18 Correct 150 ms 71268 KB Output is correct
19 Correct 151 ms 71072 KB Output is correct
20 Correct 152 ms 67740 KB Output is correct
21 Correct 144 ms 79448 KB Output is correct
22 Correct 143 ms 79708 KB Output is correct
23 Correct 158 ms 81968 KB Output is correct