Submission #1181280

#	Time	Username	Problem	Language	Result	Execution time	Memory
1181280		TudorMa	Foehn Phenomena (JOI17_foehn_phenomena)	C++20	100 / 100	99 ms	7320 KiB

foehn_phenomena

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define fi first
#define sc second
#define pb push_back
#define int long long

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef double db;
typedef pair<int, int> pii;
template<typename type>
using ordered_set = tree<type, null_type, less<type>, rb_tree_tag, tree_order_statistics_node_update>;

const int N = 2e5 + 5, mod = 1e9 + 7, inf = 2e9;
const int dl[] = {-1, 0, 1, 0}, dc[] = {0, 1, 0, -1};
const int ddl[] = {-1, -1, -1, 0, 1, 1, 1, 0}, ddc[] = {-1, 0, 1, 1, 1, 0, -1, -1};

mt19937 gen(chrono::steady_clock::now().time_since_epoch().count());
int rng(int lo = 1, int hi = INT_MAX) {
    uniform_int_distribution<int> rnd(lo, hi);
    return rnd(gen);
}

struct mint {
    int val;
    mint(int32_t x = 0) {
        val = x % mod;
    }
    mint(long long x) {
        val = x % mod;
    }
    mint operator+(mint x) {
        return val + x.val;
    }
    mint operator-(mint x) {
        return val - x.val + mod;
    }
    mint operator*(mint x) {
        return 1LL * val * x.val;
    }
    void operator+=(mint x) {
        val = (*this + x).val;
    }
    void operator-=(mint x) {
        val = (*this - x).val;
    }
    void operator*=(mint x) {
        val = (*this * x).val;
    }
    friend auto operator>>(istream& in, mint &x) -> istream& {
        in >> x.val;
        x.val %= mod;
        return in;
    }
    friend auto operator<<(ostream& out, mint const &x) -> ostream& {
        out << x.val;
        return out;
    }
};

int n, q, s, t, ans, v[N];

struct fenwick {
    int t[N];

    inline int lsb(int x) {
        return x & -x;
    }
    void update(int p, int x) {
        while(p <= n) {
            t[p] += x;
            p += lsb(p);
        }
    }
    int pref(int p) {
        int ans = v[p];
        while(p) {
            ans += t[p];
            p -= lsb(p);
        }

        return ans;
    }
} aib;

int getdiff(int p) {
    if(p == n + 1)
        return 0;
    int x = aib.pref(p-1), y = aib.pref(p);
    if(x < y)
        return (x - y) * s;
    else
        return (x - y) * t;
}

int32_t main()
{
    cin.tie(nullptr)->sync_with_stdio(0);
    
    cin >> n >> q >> s >> t;
    cin >> v[0];
    for(int i=1; i<=n; i++) {
        cin >> v[i];
        if(v[i-1] < v[i])
            ans -= (v[i] - v[i-1]) * s;
        else
            ans += (v[i-1] - v[i]) * t;
    }
    
    while(q--) {
        int l, r, c;
        cin >> l >> r >> c;
        ans -= getdiff(l);
        ans -= getdiff(r+1);
        aib.update(l, c);
        aib.update(r+1, -c);
        ans += getdiff(l);
        ans += getdiff(r+1);

        cout << ans << '\n';
    }
    return 0;
}

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