Submission #1023288

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023288		GrindMachine	Long Distance Coach (JOI17_coach)	C++17	100 / 100	113 ms	21696 KiB

coach

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

struct Line{
    ll m,c;
    ll f(ll x){
        return m*x+c;
    }
    ll intersect(Line l2){
        auto [m2,c2] = l2;
        return ceil((ld)(c2-c)/(m-m2));
    }
};

struct CHT{
    vector<pair<Line,ll>> cht;

    void insert(Line l){
        while(!cht.empty()){
            auto [l2,x] = cht.back();
            if(l.f(x) < l2.f(x)){
                cht.pop_back();
            }
            else{
                break;
            }
        }

        if(cht.empty()){
            cht.pb({l,0});
        }
        else{
            ll x = l.intersect(cht.back().ff);
            cht.pb({l,x});
        }
    }

    ll query(ll x){
        ll lo = 0, hi = sz(cht)-1;
        ll pos = -1;

        while(lo <= hi){
            ll mid = (lo+hi) >> 1;
            if(x >= cht[mid].ss){
                pos = mid;
                lo = mid+1;
            }
            else{
                hi = mid-1;
            }
        }

        assert(pos != -1);
        return cht[pos].ff.f(x);
    }
};

void solve(int test_case)
{
    ll X,n,m,W,T; cin >> X >> n >> m >> W >> T;
    vector<ll> a(n+1); // refilling points
    rep(i,n) cin >> a[i]; 
    a[n] = X;
    n++;

    auto cmp = [&](ll x, ll y){
        return x%T < y%T;
    };

    sort(all(a),cmp);

    vector<pll> b(m+1); // passengers
    rep1(i,m) cin >> b[i].ff >> b[i].ss;
    b[0] = {0,inf2};
    sort(all(b));
    m++;

    vector<ll> dp(m,inf2); // dp[i] = min cost for [0..i] if i is the last alive guy
    dp[0] = ((X-1)/T+1)*W;
    vector<ll> dp2(m,inf2);
    dp2[0] = dp[0];

    vector<ll> mnv(m,inf2);
    ll ptr = 0;

    rep(i,m){
        ll l = b[i].ff, r = inf2;
        if(i+1 < m) r = b[i+1].ff;
        while(ptr < n and a[ptr]%T <= l){
            ptr++;
        }

        while(ptr < n and a[ptr]%T < r){
            amin(mnv[i],(a[ptr++]/T)*W);
        }
    }

    vector<ll> p(m);
    rep(i,m){
        p[i] = b[i].ss;
        if(i) p[i] += p[i-1];
    }

    CHT cht;
    cht.insert({0,dp2[0]-p[0]});

    rep1(i,m-1){
        auto [d,c] = b[i];
        ll mul = mnv[i-1];

        if(mul < inf2){
            dp[i] = mul*(i-1)+p[i-1]+cht.query(mul);
        }
        else{
            ll j = i-1;
            dp[i] = mul*(i-j-1)+dp2[j]+p[i-1]-p[j];    
        }

        mul = mnv[i];

        if(mul < inf2){
            dp2[i] = mul*i+p[i]+cht.query(mul);
        }

        ll times = (X-d-1)/T+1;
        dp[i] += times*W;
        amin(dp2[i],dp[i]);

        cht.insert({-i,dp2[i]-p[i]});
    }

    ll ans = dp2[m-1];
    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 16 / 16
• Subtask 2: 30 / 30
• Subtask 3: 25 / 25
• Subtask 4: 29 / 29