Submission #850267

#	Time	Username	Problem	Language	Result	Execution time	Memory
850267		Pekiban	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	379 ms	15184 KiB

foehn_phenomena

#include <bits/stdc++.h>

using namespace std;

int _n;
const int mxN = 2e5+2;
long long st[4*mxN];
void update(int k, int x, int i = 1, int l = 0, int r = _n-1) {
    if (l == r) {
        st[i] += x;
        return;
    }
    int mid = (l + r)/2;
    if (k <= mid) {
        update(k, x, 2*i, l, mid);
    }
    else {
        update(k, x, 2*i+1, mid+1, r);
    }
    st[i] = st[2*i]+st[2*i+1];
}
long long query(int l, int r, int i = 1, int l2 = 0, int r2 = _n-1) {
    if (l <= l2 && r2 <= r) {
        return st[i];
    }
    int mid = (l2 + r2)/2;
    long long s = 0;
    if (l <= mid) {
        s += query(l, r, 2*i, l2, mid);
    }
    if (mid+1 <= r) {
        s += query(l, r, 2*i+1, mid+1, r2);
    }
    return s;
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    long long n, q, s, t;
    cin >> n >> q >> s >> t; _n = n+1;
    vector<int> a(n+1);
    long long sum = 0;
    for (int i = 0; i <= n; ++i) {
        cin >> a[i];
        if (i)  sum += (a[i] > a[i-1] ? -s*(a[i]-a[i-1]) : t*(a[i-1]-a[i]));
    }
    update(0, a[0]);
    for (int i = 1; i <= n; ++i) {
        update(i, a[i]-a[i-1]);
    }
    while (q--) {
        int l, r, x;
        cin >> l >> r >> x;
        const long long lo1 = query(0, l-1), lo2 = query(0, l); 
        update(l, x);
        sum -= (lo2 > lo1 ? -s*(lo2-lo1) : t*(lo1-lo2));
        if (r != n) {
            const long long ro1 = query(0, r), ro2 = query(0, r+1);
            sum-=(ro2 > ro1 ? -s*(ro2-ro1) : t*(ro1-ro2));
            update(r+1, -x);
        }
        const long long l1 = query(0, l-1), l2 = query(0, l);
        if (r != n) {
            const long long r2 = query(0, r+1), r1 = query(0, r);
            sum+=(r2 > r1 ? -s*(r2-r1) : t*(r1-r2));
        }
        sum+=(l2 > l1 ? -s*(l2-l1) : t*(l1-l2));
        cout << sum << '\n';
    }
}

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