Submission #47502

#	Time	Username	Problem	Language	Result	Execution time	Memory
47502		qoo2p5	Long Distance Coach (JOI17_coach)	C++14	100 / 100	256 ms	169844 KiB

coach

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

const int INF = (int) 1e9 + 1e6;
const ll LINF = (ll) 1e18 + 1e9;
const ll MOD = (ll) 1e9 + 7;

#define sz(x) (int) (x).size()
#define mp(x, y) make_pair(x, y)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lb(s, t, x) (int) (lower_bound(s, t, x) - s)
#define ub(s, t, x) (int) (upper_bound(s, t, x) - s)
#define rep(i, f, t) for (auto i = f; i < t; ++(i))
#define per(i, f, t) for (auto i = (f); i >= (t); --(i))

ll power(ll x, ll y, ll mod = MOD) {
    if (y == 0) {
        return 1;
    }
    if (y & 1) {
        return power(x, y - 1, mod) * x % mod;
    } else {
        ll tmp = power(x, y / 2, mod);
        return tmp * tmp % mod;
    }
}

template<typename A, typename B> bool mini(A &x, const B &y) {
    if (y < x) {
        x = y;
        return true;
    }
    return false;
}

template<typename A, typename B> bool maxi(A &x, const B &y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}

void add(ll &x, ll y) {
    x += y;
    if (x >= MOD) x -= MOD;
    if (x < 0) x += MOD;
}

void run();

#define TASK ""

int main() {
#ifdef LOCAL
    if (strlen(TASK) > 0) {
        cerr << "Reminder: you are using file i/o, filename: " TASK "!" << endl << endl;
    }
#endif
#ifndef LOCAL
    if (strlen(TASK)) {
        freopen(TASK ".in", "r", stdin);
        freopen(TASK ".out", "w", stdout);
    }
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
#endif
    cout << fixed << setprecision(12);
    run();
    return 0;
}

// == SOLUTION == //

const int N = (int) 2e5 + 123;

int n, m;
ll x, w, t;
ll s[N];
pair<ll, ll> p[N];
ll d[N], c[N];
int r[N];
vector<int> what[N];
ll dp[N];

struct Line {
    ll k, b;
    
    ll val(ll x) const {
        return k * x + b;
    }
};

ll div_up(ll x, ll y) {
    if (y < 0) {
        x = -x;
        y = -y;
    }
    if (x < 0) {
        return x / y;
    } else {
        return (x + y - 1) / y;
    }
}

ll inter(const Line &a, const Line &b) {
    return div_up(b.b - a.b, a.k - b.k);
}

struct CHT {
    vector<Line> lines;
    vector<ll> points;
    
    void add(const Line &l) {
        while (sz(points) && inter(l, lines.back()) <= points.back()) {
            points.pop_back();
            lines.pop_back();
        }
        if (sz(lines)) {
            points.pb(inter(l, lines.back()));
        }
        lines.pb(l);
    }
    
    ll get(ll x) {
        int pos = (int) (upper_bound(all(points), x) - points.begin());
        return lines[pos].val(x);
    }
};

CHT cht;

void run() {
    cin >> x >> n >> m >> w >> t;
    rep(i, 1, n + 1) {
        cin >> s[i];
    }
    s[n + 1] = x;
    rep(i, 1, m + 1) {
        cin >> p[i].first >> p[i].second;
    }
    sort(p + 1, p + m + 1);
    rep(i, 1, m + 1) {
        d[i] = p[i].first;
        c[i] = p[i].second;
    }
    rep(i, 0, n + 1) {
        r[i] = (int) (lower_bound(d, d + m + 1, s[i + 1] % t) - d) - 1;
        what[r[i]].pb(i);
    }
    
    dp[0] = s[n + 1] / t * w + w;
    cht.add({0, dp[0]});
    ll fee = 0;
    rep(i, 1, m + 1) {
        fee += c[i];
        dp[i] = dp[i - 1] + (s[n + 1] - d[i]) / t * w + w;
        for (int id : what[i]) {
            ll cnt = s[id + 1] / t;
            mini(dp[i], cht.get(cnt * w) + fee + i * cnt * w);
        }
        
        cht.add({-i, dp[i] - fee});
    }
    
    cout << dp[m] << "\n";
}

Compilation message (stderr)

coach.cpp: In function 'int main()':
coach.cpp:67:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(TASK ".in", "r", stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
coach.cpp:68:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(TASK ".out", "w", stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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