Submission #159409

#	Time	Username	Problem	Language	Result	Execution time	Memory
159409		thecodingwizard	Salesman (IOI09_salesman)	C++11	50 / 100	1081 ms	30456 KiB

salesman

//#pragma GCC optimize ("O3")
//#pragma GCC target ("sse4")

#include <bits/stdc++.h>

using namespace std;

template<class T> using min_heap = priority_queue<T, vector<T>, greater<T>>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define F0R1(i, a) for (int i=1; i<=(a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto& a : x)
#define MIN(a, b) a = min(a, b)
#define MAX(a, b) a = max(a, b)

#define INF 1000000010
#define LL_INF 4500000000000000000LL
#define LSOne(S) (S & (-S))
#define EPS 1e-9
#define pA first
#define pB second
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define eb emplace_back
#define PI acos(-1.0)
// #define MOD (int)(2e+9+11)
#define MOD (int)(1e+9+7)
#define SET(vec, val, size) for (int i = 0; i < size; i++) vec[i] = val;
#define SET2D(arr, val, dim1, dim2) F0R(i, dim1) F0R(j, dim2) arr[i][j] = val;
#define SET3D(arr, val, dim1, dim2, dim3) F0R(i, dim1) F0R(j, dim2) F0R(k, dim3) arr[i][j][k] = val;
#define SET4D(arr, val, dim1, dim2, dim3, dim4) F0R(i, dim1) F0R(j, dim2) F0R(k, dim3) F0R(l, dim4) arr[i][j][k][l] = val;

#define lb lower_bound
#define ub upper_bound
#define sz(x) (int)x.size()
#define beg(x) x.begin()
#define en(x) x.end()
#define all(x) beg(x), en(x)
#define resz resize
#define SORT(vec) sort(all(vec))
#define RSORT(vec) sort(vec.rbegin(),vec.rend())

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vl;

// @formatter:off
// Source: Benq (https://github.com/bqi343/USACO) [Modified]
namespace input {
    template<class T> void re(complex<T>& x);
    template<class T1, class T2> void re(pair<T1,T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, size_t SZ> void re(array<T,SZ>& a);
    template<class T> void reA(T A[], int sz);

    template<class T> void re(T& x) { cin >> x; }
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    template<class Arg, class... Args> void re(Arg& first, Args&... rest) {
        re(first); re(rest...);
    }

    template<class T1, class T2> void re(pair<T1,T2>& p) { re(p.pA,p.pB); }
    template<class T> void re(vector<T>& a) { F0R(i,sz(a)) re(a[i]); }
    template<class T, size_t SZ> void re(array<T,SZ>& a) { F0R(i,SZ) re(a[i]); }
    template<class T> void reA(T A[], int sz) { F0R(i, sz) re(A[i]); }

    void setupIO(const string &PROB = "") {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
        if (PROB.length() != 0) {
            ifstream infile(PROB + ".in");
            if (infile.good()) {
                freopen((PROB + ".in").c_str(), "r", stdin);
                freopen((PROB + ".out").c_str(), "w", stdout);
            }
        }
    }
}
using namespace input;

namespace output {
    template<class T1, class T2> void prD(const pair<T1,T2>& x);
    template<class T, size_t SZ> void prD(const array<T,SZ>& x);
    template<class T> void prD(const vector<T>& x);
    template<class T> void prD(const set<T>& x);
    template<class T1, class T2> void prD(const map<T1,T2>& x);

    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    template<class T, size_t SZ> void pr(const array<T,SZ>& x);
    template<class T> void pr(const vector<T>& x);
    template<class T> void pr(const set<T>& x);
    template<class T1, class T2> void pr(const map<T1,T2>& x);

    template<class T> void prD(const T& x) { cout << x; cout.flush(); }
    template<class Arg, class... Args> void prD(const Arg& first, const Args&... rest) {
        prD(first); prD(rest...);
    }

    template<class T1, class T2> void prD(const pair<T1,T2>& x) {
        prD("{",x.pA,", ",x.pB,"}");
    }
    template<class T> void prDContain(const T& x) {
        prD("{");
        bool fst = 1; for (const auto& a: x) prD(!fst?", ":"",a), fst = 0; // const needed for vector<bool>
        prD("}");
    }
    template<class T, size_t SZ> void prD(const array<T,SZ>& x) { prDContain(x); }
    template<class T> void prD(const vector<T>& x) { prDContain(x); }
    template<class T> void prD(const set<T>& x) { prDContain(x); }
    template<class T1, class T2> void prD(const map<T1,T2>& x) { prDContain(x); }

    void psD() { prD("\n"); }
    template<class Arg> void psD(const Arg& first) {
        prD(first); psD(); // no space at end of line
    }
    template<class Arg, class... Args> void psD(const Arg& first, const Args&... rest) {
        prD(first," "); psD(rest...); // print w/ spaces
    }


    template<class T> void pr(const T& x) { cout << x; }
    template<class Arg, class... Args> void pr(const Arg& first, const Args&... rest) {
        pr(first); pr(rest...);
    }

    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr(x.pA, " ", x.pB);
    }
    template<class T> void prContain(const T& x) {
        bool fst = 1; for (const auto& a: x) pr(!fst?" ":"",a), fst = 0; // const needed for vector<bool>
    }
    template<class T, size_t SZ> void pr(const array<T,SZ>& x) { prContain(x); }
    template<class T> void pr(const vector<T>& x) { prContain(x); }
    template<class T> void pr(const set<T>& x) { prContain(x); }
    template<class T1, class T2> void pr(const map<T1,T2>& x) { prContain(x); }

    void ps() { pr("\n"); }
    template<class Arg> void ps(const Arg& first) {
        pr(first); ps(); // no space at end of line
    }
    template<class Arg, class... Args> void ps(const Arg& first, const Args&... rest) {
        pr(first," "); ps(rest...); // print w/ spaces
    }
}
using namespace output;
// @formatter:on

/* ============================ */

class MaxSegTree {
private:
    int st[500001*4];

public:
    MaxSegTree(int n, int v) {
        SET(st, v, 4*n);
    }

    int qry(int p, int i, int j, int l, int r) {
        if (i >= l && j <= r) return st[p];
        if (i > r || j < l) return -INF;
        return max(qry(p << 1, i, (i+j)/2, l, r), qry((p << 1) + 1, (i+j)/2+1, j, l, r));
    }

    int upd(int p, int i, int j, int k, int v) {
        if (i == j && i == k) {
            st[p] = v;
            return st[p];
        }
        if (i > k || j < k) return st[p];
        return st[p] = max(upd(p << 1, i, (i+j)/2, k, v), upd((p << 1) + 1, (i+j)/2+1, j, k, v));
    }
};

struct fair {
    int day, loc, val;
};
bool operator<(const fair &a, const fair &b) { return a.day < b.day; }

int dp[500000]; // max $ ending on fair i
int dp1[500000];
int dp2[500000];
vector<fair> fairs;

int mxD = 500001;
MaxSegTree upstream(mxD, -INF), downstream(mxD, -INF);

int main() {
    setupIO();

    int n, u, d, s; re(n, u, d, s);
    F0R(i, n) {
        int t, l, m; re(t, l, m);
        fairs.pb({t, l-1, m});
    }
    sort(all(fairs));

    downstream.upd(1, 0, mxD-1, s-1, 0-(mxD-(s-1))*d);
    upstream.upd(1, 0, mxD-1, s-1, 0-(s-1)*u);
    F0R(i, n) {
        int si = i;
        vector<fair> ff; ff.pb(fairs[i]);
        while (i+1<n && fairs[i+1].day == ff.back().day) {
            ff.pb(fairs[++i]);
        }
        sort(all(ff), [](const fair &l, const fair &r) { return l.loc < r.loc;  });
        FOR(j, si, i+1) {
            fair f = ff[j-si];
            int loc = f.loc;
            int bestDownstream = downstream.qry(1, 0, mxD-1, 0, loc) + (mxD-loc)*d;
            int bestUpstream = upstream.qry(1, 0, mxD-1, loc, mxD-1) + loc*u;
            dp1[j] = max(bestDownstream, bestUpstream) + f.val;
            if (j != si) {
                dp1[j] = max(dp1[j], dp1[j-1] - (f.loc-ff[j-si-1].loc)*u + f.val);
            }
        }
        FORd(j, si, i+1) {
            fair f = ff[j-si];
            int loc = f.loc;
            int bestDownstream = downstream.qry(1, 0, mxD-1, 0, loc) + (mxD-loc)*d;
            int bestUpstream = upstream.qry(1, 0, mxD-1, loc, mxD-1) + loc*u;
            dp2[j] = max(bestDownstream, bestUpstream) + f.val;
            if (j != i) {
                dp2[j] = max(dp2[j], dp2[j+1] - (-f.loc+ff[j-si+1].loc)*d + f.val);
            }
        }
        FOR(j, si, i+1) {
            dp[j] = max(dp1[j], dp2[j]);
            int loc = ff[j-si].loc;
            downstream.upd(1, 0, mxD-1, loc, dp[j]-(mxD-loc)*d);
            upstream.upd(1, 0, mxD-1, loc, dp[j]-loc*u);
        }
    }

    int best = 0;
    F0R(i, n) {
        int loc = fairs[i].loc;
        if (loc > s-1) {
            MAX(best, dp[i] - (loc-(s-1))*u);
        } else {
            MAX(best, dp[i] - (s-1-loc)*d);
        }
    }
    ps(best);

    return 0;
}

Compilation message (stderr)

salesman.cpp: In function 'void input::setupIO(const string&)':
salesman.cpp:85:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
                 freopen((PROB + ".in").c_str(), "r", stdin);
                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
salesman.cpp:86:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
                 freopen((PROB + ".out").c_str(), "w", stdout);
                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 50 / 100