Submission #1129020

#	Time	Username	Problem	Language	Result	Execution time	Memory
1129020		ljtunas	Construction of Highway (JOI18_construction)	C++20	7 / 100	2094 ms	568 KiB

construction

// author : anhtun_hi , nqg
// 25-26.12.2024

#include <bits/stdc++.h>
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define reset(h, v)    memset(h, v, sizeof h)
#define Forv(i, a)     for(auto& i : a)
#define For(i, a, b)   for(int i = a; i <= b; ++i)
#define Ford(i, a, b)  for(int i = a; i >= b; --i)
#define c_bit(i)     __builtin_popcountll(i)
#define Bit(mask, i)    ((mask >> i) & 1LL)
#define onbit(mask, i)  ((mask) bitor (1LL << i))
#define offbit(mask, i) ((mask) &~ (1LL << i))
#define Log2(x) (63 - __builtin_clzll(x))
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
using namespace std;

using ll = long long;
using ii = pair<ll, ll>;
using db = long double;
using ull = unsigned long long;

namespace std {
    template <typename T, int D>
    struct _vector : public vector <_vector <T, D - 1>> {
        static_assert(D >= 1, "Dimension must be positive!");
        template <typename... Args>
        _vector(int n = 0, Args... args) : vector <_vector <T, D - 1>> (n, _vector <T, D - 1> (args...)) {}
    };
    template <typename T> struct _vector <T, 1> : public vector <T> {
        _vector(int n = 0, const T& val = T()) : vector <T> (n, val) {}
    };
    template <class A, class B> bool minimize(A &a, B b){return a > b ? a = b, true : false;}
    template <class A, class B> bool maximize(A &a, B b){return a < b ? a = b, true : false;}
}
const int dx[] = {0, 0, +1, -1}, dy[] = {-1, +1, 0, 0}, LOG = 20, base = 311, inf = 1e9 + 5;
const int MAXN = 1e5 + 5;
const  ll  mod = 1e9 + 7;
const  ll   oo = 1e18;

//#define int long long

int n, c[MAXN], p[MAXN];

struct Edge{
    int u, v;
} E[MAXN];

void Solve() {
    cin >> n;
    vector<int> compress;
    For(i, 1, n) cin >> c[i], compress.push_back(c[i]);
    sort(all(compress)), compress.resize(unique(all(compress)) - compress.begin());
    For(i, 1, n) c[i] = lower_bound(all(compress), c[i]) - compress.begin() + 1;
    For(i, 1, n - 1){
        cin >> E[i].u >> E[i].v;
        p[E[i].v] = E[i].u;
    }

    For(i, 1, n - 1){
        int u = E[i].u;
        int v = E[i].v;
        vector<int> List;
        while(u){
            List.push_back(u);
            u = p[u];
        }
        reverse(all(List));
        int ans = 0;
        For(j, 0, List.size() - 1) For(k, j + 1, List.size() - 1){
            ans += c[List[j]] > c[List[k]];
        }
        Forv(x, List) c[x] = c[v];
//        if (i == 9) Forv(x, List) cerr << x << '\n';
        cout << ans << '\n';
    }

}

signed main() {
    cin.tie(0) -> sync_with_stdio(0);
    if(fopen("JOI18_construction.inp", "r")) {
        freopen("JOI18_construction.inp", "r", stdin);
        freopen("JOI18_construction.out", "w", stdout);
    }

    int t = 1;
//    cin >> t;
    while(t --) Solve();
    return 0;
}

Compilation message (stderr)

construction.cpp: In function 'int main()':
construction.cpp:85:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |         freopen("JOI18_construction.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
construction.cpp:86:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |         freopen("JOI18_construction.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 0 / 9
• Subtask 3: 0 / 84