Submission #999912

#	Time	Username	Problem	Language	Result	Execution time	Memory
999912		vjudge1	Construction of Highway (JOI18_construction)	C++17	16 / 100	2024 ms	9116 KiB

construction

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define pii pair<int, int>
#define all(v) v.begin(), v.end()
#define oo 1e9
const int MAX = 1e5 + 5;

int n;

int tree[MAX];

void init(){
    for(int i = 0; i < MAX; i++) tree[i] = 0;
}

void update(int pos, int val){
    for(int i = pos; i < MAX; i += (i & -i)) tree[i] += val;
}

int ask(int l, int r){
    if(l != 1) return ask(1, r) - ask(1, l - 1);
    int res = 0;
    for(int i = r; i >= 1; i -= i & -i) res += tree[i];
    return res;
}

vector<int> g[MAX];
int c[MAX];
int par[MAX];

void solve(){
    cin >> n;
    vector<pii> v;
    for(int i = 1; i <= n; i++){
        cin >> c[i];
        v.push_back({c[i], i});
    }
    sort(v.begin(), v.end());
    int t = 0;
    for(int i = 0; i < v.size(); i++){
        if(i == 0 || v[i].first != v[i - 1].first) t++;
        c[v[i].second] = t;
    }
    par[1] = 1;
    for(int i = 1; i < n; i++){
        int u, v; cin >> u >> v;
        par[v] = u;
        int ans = 0;
        while(1){
            ans += ask(1, c[u] - 1);
            update(c[u], 1);
            c[u] = c[v];
            if(u == 1) break;
            u = par[u];
        }
        init();
        cout << ans << '\n';
    }
}

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
    while(t--){
        solve();
    }
}

Compilation message (stderr)

construction.cpp: In function 'void solve()':
construction.cpp:43:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |     for(int i = 0; i < v.size(); i++){
      |                    ~~^~~~~~~~~~

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