Submission #113638

#	Time	Username	Problem	Language	Result	Execution time	Memory
113638		popovicirobert	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	206 ms	12308 KiB

foehn_phenomena

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44

using namespace std;

struct Fenwick {
    vector <ll> aib;
    int n;

    inline void init(int _n) {
        n = _n;
        aib.resize(n + 1, 0);
    }

    inline void update(int pos, int val) {
        for(int i = pos; i <= n; i += lsb(i)) {
            aib[i] += val;
        }
    }

    inline ll query(int pos) {
        ll ans = 0;
        for(int i = pos; i > 0; i -= lsb(i)) {
            ans += aib[i];
        }
        return ans;
    }

};

inline ll get(ll h1, ll h2, int s, int t) {
    if(h1 < h2) return -1LL * (h2 - h1) * s;

    return 1LL * (h1 - h2) * t;
}


int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, n, q, s, t;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> q >> s >> t;

    ll cur = 0;

    vector <int> a(n + 2);
    for(i = 1; i <= n + 1; i++) {
        cin >> a[i];
        if(i > 1) {
            cur += get(a[i - 1], a[i], s, t);
        }
    }

    Fenwick fen; fen.init(n + 1);

    while(q > 0) {
        q--;

        int l, r, x;

        cin >> l >> r >> x;
        l++, r++;

        if(l > 1) {
            cur -= get(a[l - 1] + fen.query(l - 1), a[l] + fen.query(l), s, t);
        }
        if(r <= n) {
            cur -= get(a[r] + fen.query(r), a[r + 1] + fen.query(r + 1), s, t);
        }

        fen.update(l, x);
        fen.update(r + 1, -x);

        if(l >= 1) {
            cur += get(a[l - 1] + fen.query(l - 1), a[l] + fen.query(l), s, t);
        }
        if(r <= n) {
            cur += get(a[r] + fen.query(r), a[r + 1] + fen.query(r + 1), s, t);
        }

        cout << cur << "\n";
    }

    //cin.close();
    //cout.close();
    return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 10 / 10
• Subtask 3: 60 / 60