Submission #893833

#	Time	Username	Problem	Language	Result	Execution time	Memory
893833		kigash	Evacuation plan (IZhO18_plan)	C++17	100 / 100	666 ms	79932 KiB

plan

#include "bits/stdc++.h"
using namespace std;       

// #pragma comment(linker, "/stack:200000000")
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")

using ll = long long;
using ld = long double;
#define pb push_back
#define ff first
#define ss second
#define sz(x) (ll)(x).size()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
void IOIGold2024_InshAllah() { ios_base::sync_with_stdio(false); cin.tie(NULL); }
ll binmul(ll a, ll b, ll c) { ll res = 0; while(b) { if(b&1) (res += a) %= c; (a += a) %= c; b >>= 1; } return res; }
ll binpow(ll a, ll b, ll c) { ll res = 1; while(b) { if(b&1) (res *= a) %= c; (a *= a) %= c; b >>= 1; } return res; }
template<typename T> T gcd(T a, T b) { if(b==0) return a; return gcd(b, a%b); }
template<typename T> T lcm(T a, T b) { return a/gcd(a, b)*b; }
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ld rnd() { return rng()%INT_MAX*1.0/INT_MAX; }

const ll inf = 1e18+7, MX = LLONG_MAX, MN = LLONG_MIN;
const ll mod = 1e9+7, N = 5e5+5;
struct que { ll u, v; } c[N];
vector<pair<ll, ll>> g[N], t;
vector<pair<ll*, ll>> upd;
ll d[N], ans[N], u[N], v[N], w[N], p[N], sz[N];

ll get(ll x) {
    while(p[x]!=-1) x = p[x];
    return x;
}

void update(ll x, ll y) {
    x = get(x), y = get(y);
    if(x==y) return;
    if(sz[x]>sz[y]) {
        upd.emplace_back(&p[y], p[y]);
        p[y] = x;
    }
    else if(sz[x]<sz[y]) {
        upd.emplace_back(&p[x], p[x]);
        p[x] = y;
    }
    else {
        upd.emplace_back(&p[x], p[x]);
        upd.emplace_back(&sz[y], sz[y]);
        p[x] = y, sz[y]++;
    }
}

void solve(ll l, ll r, vector<ll> a) {
    if(l==r-1 || a.empty()) {
        for(auto x: a) ans[x] = t[l].ff;
        return;
    }
    ll mid = l+(r-l)/2, st = sz(upd);
    for(ll i=l; i<mid; i++) {
        update(u[t[i].ss], v[t[i].ss]);
    }
    vector<ll> lt, rt;
    for(auto x: a) {
        // cout<<l<<" "<<r<<" - "<<x<<"\n";
        if(get(c[x].u)==get(c[x].v)) lt.pb(x);
        else rt.pb(x);
    }
    solve(mid, r, rt);
    while(sz(upd)>st) {
        *upd.back().ff = upd.back().ss;
        upd.pop_back();
    }
    solve(l, mid, lt);
}

void kigash() {
    ll n, m, k, q;
    cin>>n>>m;
    for(ll i=1; i<=m; i++) {
        cin>>u[i]>>v[i]>>w[i];
        g[u[i]].pb({v[i], w[i]}), g[v[i]].pb({u[i], w[i]});
    }
    cin>>k;
    set<pair<ll, ll>> st;
    for(ll i=1; i<=n; i++) d[i] = inf, p[i] = -1;
    while(k--) {
        ll v;
        cin>>v;
        st.insert({0, v}), d[v] = 0;
    }
    while(!st.empty()) {
        ll v = (*st.begin()).ss;
        st.erase(st.begin());
        for(auto [to, w]: g[v]) {
            if(d[to]>d[v]+w) {
                st.erase({d[to], to});
                d[to] = d[v]+w;
                st.insert({d[to], to});
            }
        }
    }
    for(ll i=1; i<=m; i++) {
        t.pb({min(d[u[i]], d[v[i]]), i});
    }
    sort(rall(t));
    // for(auto [x, y]: t) cout<<x<<" ";
    cin>>q;
    vector<ll> tmp;
    for(ll i=1; i<=q; i++) {
        tmp.pb(i);
        cin>>c[i].u>>c[i].v;
    }
    solve(0, sz(t), tmp);
    for(ll i=1; i<=q; i++) cout<<ans[i]<<"\n";
    return;
}

signed main(/*Kigash Amir*/) {
    // freopen("");
    IOIGold2024_InshAllah();
    ll tt = 1;
    // cin>>tt;
    for(ll i=1; i<=tt; i++) {
        kigash();
    }
}

Compilation message (stderr)

plan.cpp: In function 'void freopen(std::string)':
plan.cpp:17:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
      |                          ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
plan.cpp:17:73: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
      |                                                                  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46