Submission #1144143

#	Time	Username	Problem	Language	Result	Execution time	Memory
1144143		Shadow1	Rigged Roads (NOI19_riggedroads)	C++20	0 / 100	645 ms	46008 KiB

riggedroads

// Programmer: Shadow1

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
using namespace std;

using ll = long long;
using ld = long double;
using ull = unsigned long long;
using str = string; // yay python!

#define i64 int64_t
#define show(x) cerr << (#x) << " = " << (x) << '\n';
#define output_vector(v) for(auto &x : v){cout << x << ' ';}cout << '\n';
#define output_pairvector(v) for(auto &x : v){cout << x.first << " " << x.second << '\n';}
#define read_vector(v) for(auto &x : v){cin >> x;}
#define vt vector
#define prq priority_queue
#define pb push_back
#define eb emplace_back
#define pii pair<int,int>
#define fir first
#define sec second
#define sz(x) ll(x.size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define int long long
#define discretize(x) sort(x.begin(), x.end()); x.erase(unique(x.begin(), x.end()), x.end());

// Riggedroads

int n, m;
int w = 1;
const int maxn = 3e5 + 5;
vector<pii> e(maxn), adj[maxn], par(maxn);
vector<int> dep(maxn), ans(maxn), r(maxn);
vector<bool> vis(maxn); // visited edges

void dfs(int u, int p) {
    for(auto &v : adj[u]) {
        if(v.fir == p) continue;
        dep[v.fir] = dep[u] + 1;
        par[v.fir].fir = u;
        par[v.fir].sec = v.sec;
        dfs(v.fir, u);
    }
}

void ban(int u, int v, int k) {  // deactivate edge (u, v)
    if(u == v || u == 0) return;
    // assume u is parent of v i.e. par[v] = u
    if(dep[u] > dep[v]) swap(u, v);
    par[v] = par[u];
    vis[k] = true;
}

void move(int u, int v) {
    // if(same(u, v)) return;
    vector<int> span;
    while(dep[v] > dep[u]) {
        span.push_back(par[v].sec);
        int op = par[v].fir;
        ban(par[v].fir, v, par[v].sec);
        v = op;
    }
    while(dep[u] > dep[v]) {
        span.push_back(par[u].sec);
        int op = par[u].fir;
        ban(par[u].fir, u, par[u].sec);
        u = op;
    }
    while(u != v) {
        int temp = u;
        span.push_back(par[u].sec);
        int op = par[u].fir;
        ban(par[u].fir, u, par[u].sec);
        u = op;
        span.push_back(par[v].sec);
        op = par[v].fir;
        ban(par[v].fir, v, par[v].sec);
        v = op;
    }
    sort(all(span));
    for(auto &e : span) {
        if(e != -1)
            ans[e] = w++;
    }
}

void solve() {
    cin >> n >> m;
    for(int i=0; i<m; ++i) {
        int a, b;
        cin >> a >> b;
        e[i] = {a, b};
    }
    vector<bool> keep(m);
    for(int i=0; i<n-1; ++i) {
        cin >> r[i];
        r[i]--;
        keep[r[i]] = true;
    }
    for(int i=0; i<m; ++i) {
        if(keep[i]) {
            int a = e[i].fir, b = e[i].sec;
            adj[a].push_back({b, i});
            adj[b].push_back({a, i});
        }
    }
    par[1] = {0, -1};
    dep[1] = 1;
    dfs(1, 0);
    for(int i=0; i<m; ++i) {
        show(i);
        if(vis[i]) continue;
        int u = e[i].fir, v = e[i].sec;
        if(keep[i]) {
            ban(u, v, i);
            ans[i] = w++;
        } else {
            move(u, v);
            ans[i] = w++;
        }
    }
    for(int i=0; i<m; ++i)
        cout << ans[i] << " ";
}



// CHECK YOUR OVERFLOWS!!!! 
signed main() {
    // freopen("output.txt", "w", stdout);
    // freopen("input.txt", "r", stdin);
    ios::sync_with_stdio(false);
    cin.tie(NULL); 
    int T = 1;
    // cin >> T;
    for(int tc = 1; tc <= T; ++tc) {
        // cout << "Case #" << tc << ": ";
        solve();
    }

    return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 19
• Subtask 3: 0 / 9
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 12
• Subtask 7: 0 / 32