Submission #254273

#	Time	Username	Problem	Language	Result	Execution time	Memory
254273		karma	Holiday (IOI14_holiday)	C++14	100 / 100	2339 ms	19220 KiB

holiday

#include <bits/stdc++.h>
#define pb          emplace_back
#define ll          long long
#define fi          first
#define se          second
#define mp          make_pair
//#define int         int64_t

using namespace std;

const int N = int(1e5) + 7;
typedef pair<ll, int> pii;

pii operator + (const pii& x, const pii& y) {
    return pii(x.fi + y.fi, x.se + y.se);
}
struct TSegment {
    vector<int> l, h;
    vector<pii> st;
    TSegment() {}
    void init(int n) {
        l.resize(4 * n + 4);
        h.resize(l.size());
        st.resize(l.size());
        build(1, 0, n - 1);
    }
    void reset() {
        fill(st.begin(), st.end(), pii(0, 0));
    }
    void build(int x, int low, int high) {
        l[x] = low, h[x] = high, st[x] = pii(0, 0);
        if(l[x] == h[x]) return;
        int mid = low + high >> 1;
        build(x << 1, low, mid);
        build(x << 1 | 1, mid + 1, high);
    }
    void upd(int x, int pos, int val, int s) {
        if(l[x] > pos || h[x] < pos) return;
        if(l[x] == h[x]) {
            st[x].fi += val;
            st[x].se += s;
            return;
        }
        upd(x << 1, pos, val, s);
        upd(x << 1 | 1, pos, val, s);
        st[x] = st[x << 1] + st[x << 1 | 1];
    }
    ll get(int x, int k) {
        if(k < 0) return 0;
        if(k >= st[x].se) return st[x].fi;
        if(l[x] == h[x]) return 0;
        if(st[x << 1].se >= k) return get(x << 1, k);
        return st[x << 1].fi + get(x << 1 | 1, k - st[x << 1].se);
    }
} it;

const int M = 3 * N;
ll f[2][M], g[2][M];
int s;
vector<int> id, pos, val;

int L = -1, R = -1;

pair<ll, ll> cost(int d, int l, int r) {
    if(L == -1 && R == -1) L = l, R = L - 1;
    while(L < l) it.upd(1, pos[L], -val[L], -1), ++L;
    while(L > l) --L, it.upd(1, pos[L], val[L], 1);
    while(R > r) it.upd(1, pos[R], -val[R], -1), --R;
    while(R < r) ++R, it.upd(1, pos[R], val[R], 1);
    return mp(it.get(1, d - r + l), it.get(1, d - 2 * (r - l)));
}

void dp(int cur, int l, int r, int optl, int optr) {
    if(l > r || optl > optr) return;
    int m = l + r >> 1, optm = optl;
    ll cf, cg;
    f[cur][m] = 0, g[cur][m] = 0;
    for(int i = optl; i <= optr; ++i) {
        tie(cf, cg) = cost(m, s, i);
        if(cf > f[cur][m]) optm = i, f[cur][m] = cf;
        if(cg > g[cur][m]) g[cur][m] = cg;
    }
    dp(cur, l, m - 1, optl, optm);
    dp(cur, m + 1, r, optm, optr);
}

void dpg(int cur, int l, int r, int optl, int optr) {
    if(l > r || optl > optr) return;
    int m = l + r >> 1, optm = optl;
    ll cf, cg;
    g[cur][m] = 0;
    for(int i = optl; i <= optr; ++i) {
        tie(cf, cg) = cost(m, s, i);
        if(cg > g[cur][m]) optm = i, g[cur][m] = cg;
    }
    dpg(cur, l, m - 1, optl, optm);
    dpg(cur, m + 1, r, optm, optr);
}

ll findMaxAttraction(int n, int start, int d, int attraction[]) {
   val.resize(n); pos.resize(n);
   id.resize(n); iota(id.begin(), id.end(), 0);
   copy(attraction, attraction + n, val.begin());
   sort(id.begin(), id.end(), [&](const int& x, const int& y) {
            return val[x] > val[y];
        });
   for(int i = 0; i < n; ++i) pos[id[i]] = i;
   it.init(n);
   s = start + 1; dp(0, 0, d, s, n - 1);
   dpg(0, 0, d, s, n - 1);
   for(int i = n - 1; i >= 0; --i) val[i] = attraction[n - i - 1];
   sort(id.begin(), id.end(), [&](const int& x, const int& y) {
            return val[x] > val[y];
        });
   for(int i = 0; i < n; ++i) pos[id[i]] = i;
   it.reset(); L = R = -1;
   s = n - start - 1; dp(1, 0, d, s, n - 1);
   dpg(1, 0, d, s, n - 1);
   ll res = max(f[0][d - 1], f[1][d]);
   for(int i = 0; i <= d; ++i){
        if(d - i - 2 >= 0) {
            res = max(res, g[0][i] + f[1][d - i - 2]);
        }
        if(d - i - 1 >= 0) res = max(res, f[0][i] + g[1][d - i - 1]);
   }
   return res;
}

//int a[N];
//
//int32_t main() {
//    ios_base::sync_with_stdio(0);
//    cin.tie(0), cout.tie(0);
//    #define Task        "test"
//    if(fopen(Task".inp", "r")) {
//        freopen(Task".inp", "r", stdin);
//        freopen(Task".out", "w", stdout);
//    }
//    int n, start, d;
//    cin >> n >> start >> d;
//    for(int i = 0; i < n; ++i) cin >> a[i];
//    cout << findMaxAttraction(n, start, d, a);
//}

Compilation message (stderr)

holiday.cpp: In member function 'void TSegment::build(int, int, int)':
holiday.cpp:33:23: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
         int mid = low + high >> 1;
                   ~~~~^~~~~~
holiday.cpp: In function 'void dp(int, int, int, int, int)':
holiday.cpp:75:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int m = l + r >> 1, optm = optl;
             ~~^~~
holiday.cpp: In function 'void dpg(int, int, int, int, int)':
holiday.cpp:89:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int m = l + r >> 1, optm = optl;
             ~~^~~

• Subtask 1: 7 / 7
• Subtask 2: 23 / 23
• Subtask 3: 17 / 17
• Subtask 4: 53 / 53