Submission #516112

#	Time	Username	Problem	Language	Result	Execution time	Memory
516112		Jeff12345121	Pinball (JOI14_pinball)	C++17	11 / 100	483 ms	524292 KiB

pinball

#include <bits/stdc++.h>
#define ll long long
#define int long long
using namespace std;

#ifdef EVAL
#define in cin
#define out cout
#else
ifstream in("in.in");
ofstream out("out.out");
#endif

int n, m;
const ll inf = (1LL << 60);
struct Dev {
    int l, r, hole, cost;
};
vector<Dev> dev;

struct SegTree {
    int l, r;
    ll val;  /// val = min
    SegTree *lChild, *rChild;

    SegTree(){}
    SegTree(int l, int r) : l(l), r(r) {
        if (l == r) {
            val = inf;
        } else {
            int mij = (l + r) / 2;
            lChild = new SegTree(1, mij);
            rChild = new SegTree(mij + 1, r);
            recalc();
        }
    }

    void recalc() {
        val = min(lChild->val, rChild->val);
    }
    void update(int p, ll newVal) {
        if (p < l || p > r) return;

        if (l == p && r == p) {
            val = min(val, newVal);
            return;
        }

        lChild->update(p, newVal);
        rChild->update(p, newVal);
        recalc();
    }

    ll query(int ql, int qr) {
        if (qr < l || ql > r) return inf;

        if (ql <= l && r <= qr) {
            return val;
        }

        return min(lChild->query(ql, qr), rChild->query(ql, qr));
    }
};

SegTree segTreeLeft,segTreeRight;

template <typename F>
void getDp(vector<ll> &dp, F f) {
    /// we want to have all the pinballs take it past left
    // dp[i] = minCost to get all balls to this device
    segTreeLeft = SegTree(1, n);
    dp.resize(m + 1);
    for (int i = 1; i <= m; i++) {
        dp[i] = inf;
    }
    ll ans = inf;
    for (int i = 1; i <= m; i++) {
        if (f(dev[i])) {
            dp[i] = dev[i].cost;
        }
        dp[i] = min(dp[i], dev[i].cost + segTreeLeft.query(dev[i].l, dev[i].r));
        segTreeLeft.update(dev[i].hole, dp[i]);
    }
}
set<int> values;
map<int, int> valToNorm;
int32_t main() {
    in >> m >> n;
    /// m is number of lines, n is number of collumns

    vector<pair<int, int>> sortDev;
    sortDev.resize(m + 1);
    dev.resize(m + 1);
    for (int i = 1; i <= m; i++) {
        int l, r, hole, cost;
        in >> l >> r >> hole >> cost;
        values.insert(l);
        values.insert(r);
        values.insert(hole);
        dev[i] = {l, r, hole, cost};

        sortDev[i] = {l, r};
    }

    sort(sortDev.begin(), sortDev.end());

    {
        int r = 1;
        for (int i = 1; i <= m; i++) {
            if (sortDev[i].first > r) {
                out << "-1\n";
                return 0;
            }
            r = max(r, sortDev[i].second);
        }

        if (r < n) {
            out << "-1\n";
            return 0;
        }
    }

    sortDev.clear();

    int nr = 0;
    for (auto k : values) {
        valToNorm[k] = ++nr;
    }

    for (int i = 1; i <= m; i++) {
        dev[i].l = valToNorm[dev[i].l];
        dev[i].r = valToNorm[dev[i].r];
        dev[i].hole = valToNorm[dev[i].hole];
    }

    valToNorm.clear();
    values.clear();

    n = nr;

    vector<ll> leftDp, rightDp;
    getDp(leftDp, [&](Dev x) {
        return x.l == 1;
    });

    getDp(rightDp, [&](Dev x) {
        return x.r == n;
    });

    segTreeLeft = SegTree(1, n);
    segTreeRight = SegTree(1, n);
    ll ans = inf;
    for (int i = 1; i <= m; i++) {
        /// i is middle
        ll leftCost = inf, rightCost = inf;
        if (dev[i].l > 1) {
            leftCost = segTreeLeft.query(dev[i].l, dev[i].r);
        } else {
            leftCost = 0;
        }

        if (dev[i].r < n) {
            rightCost = segTreeRight.query(dev[i].l, dev[i].r);
        } else {
            rightCost = 0;
        }

        segTreeLeft.update(dev[i].hole, leftDp[i]);
        segTreeRight.update(dev[i].hole, rightDp[i]);

        ans = min(ans, leftCost + rightCost + dev[i].cost);
        // cout << "\n";
    }

    if (ans == inf) {
        out << "-1\n";
    } else {
        out << ans << "\n";
    }
}

Compilation message (stderr)

pinball.cpp: In instantiation of 'void getDp(std::vector<long long int>&, F) [with F = main()::<lambda(Dev)>]':
pinball.cpp:144:6:   required from here
pinball.cpp:76:8: warning: unused variable 'ans' [-Wunused-variable]
   76 |     ll ans = inf;
      |        ^~~
pinball.cpp: In instantiation of 'void getDp(std::vector<long long int>&, F) [with F = main()::<lambda(Dev)>]':
pinball.cpp:148:6:   required from here
pinball.cpp:76:8: warning: unused variable 'ans' [-Wunused-variable]

• Subtask 1: 11 / 11
• Subtask 2: 0 / 18
• Subtask 3: 0 / 22
• Subtask 4: 0 / 49