Submission #1109300

#	Time	Username	Problem	Language	Result	Execution time	Memory
1109300		mariaclara	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	280 ms	24924 KiB

foehn_phenomena

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef tuple<ll,ll,ll> trio;
typedef pair<int,int> pii;
const int MAXN = 2e5+5;
const ll INF = 1e9;
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
#define mk make_pair
#define pb push_back
#define fr first
#define sc second

int n, q, s, t, a[MAXN];
ll ans, seg[4*MAXN], lazy[4*MAXN], dif[MAXN];

void build(int node, int l, int r) {
    if(l == r) {
        seg[node] = a[l];
        return;
    }

    int mid = (l+r)/2;
    build(2*node, l, mid);
    build(2*node+1, mid+1, r);
}

void prop(int node, int flag) {
    seg[node] += lazy[node];

    if(!flag) {
        lazy[2*node] += lazy[node];
        lazy[2*node+1] += lazy[node];
    }

    lazy[node] = 0;
}

void update(int node, int l, int r, int p, int q, int x) {
    prop(node, l==r);

    if(r < p or q < l) return;
    if(p <= l and r <= q) {
        lazy[node] = x;
        prop(node, l==r);
        return;
    } 

    int mid = (l+r)/2;
    update(2*node, l, mid, p, q, x);
    update(2*node+1, mid+1, r, p, q, x);
}

ll query(int node, int l, int r, int ind) {
    prop(node, l == r);
    if(ind == 0) return 0;
    if(l == r) return seg[node];

    int mid = (l+r)/2;
    if(ind <= mid) return query(2*node, l, mid, ind);
    else return query(2*node+1, mid+1, r, ind);
}
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

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

    for(int i = 0; i <= n; i++) {
        cin >> a[i];
        if(i == 0) continue;
        if(a[i] > a[i-1]) dif[i] = (ll)(a[i-1] - a[i]) * s;
        else dif[i] = (ll)(a[i-1] - a[i]) * t;
        ans += dif[i];
    }


    build(1, 1, n);

    while(q--) {
        int L, R, X;
        cin >> L >> R >> X;

        update(1, 1, n, L, R, X);

        ans -= dif[L];
        dif[L] = query(1, 1, n, L-1) - query(1, 1, n, L);

        if(dif[L] < 0) dif[L] *= s;
        else dif[L] *= t;
        ans += dif[L];

        ans -= dif[R+1];
        dif[R+1] = query(1, 1, n, R) - query(1, 1, n, min(R+1, n));
        
        if(dif[R+1] < 0) dif[R+1] *= s;
        else dif[R+1] *= t;
        ans += dif[R+1];

        cout << ans << "\n";
    }
}

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