Submission #1095602

#	Time	Username	Problem	Language	Result	Execution time	Memory
1095602		TrinhKhanhDung	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	111 ms	12452 KiB

foehn_phenomena

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(),v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define oo (ll)1e18 + 10
#define INF (ll)1e9
#define MOD (ll)(1e9 + 7)

using namespace std;

template<class T1, class T2>
    bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}

template<class T1, class T2>
    bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}

template<class T1, class T2>
    void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}

template<class T1, class T2>
    void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}

template<class T>
    void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}

struct fen{
    vector<ll> tree;
    int n;

    fen(int _n = 0){
        n = _n;
        tree.resize(n + 3, 0);
    }

    void upd(int p, ll c){
        for(; p <= n; p += p & -p) tree[p] += c;
    }

    ll get(int p){
        ll ans = 0;
        for(; p > 0; p -= p & -p) ans += tree[p];
        return ans;
    }
};

const int maxN = 2e5 + 10;

int N, Q, S, T;
int a[maxN];

void solve(){
    cin >> N >> Q >> S >> T;
    for(int i = 0; i <= N; i++) cin >> a[i];

    ll larger = 0, smaller = 0;
    fen bit(N);
    for(int i = 1; i <= N; i++){
        bit.upd(i, a[i]);
        bit.upd(i + 1, -a[i]);
        if(a[i] > a[i - 1]) larger += a[i] - a[i - 1];
        else smaller += a[i - 1] - a[i];
    }

    while(Q--){
        int l, r, x; cin >> l >> r >> x;

        ll val_l = bit.get(l);
        ll pre_l = bit.get(l - 1);
        if(val_l > pre_l) larger -= val_l - pre_l;
        else smaller -= pre_l - val_l;

        ll val_r = bit.get(r);
        ll nxt_r = bit.get(r + 1);
        if(r < N){
            if(nxt_r > val_r) larger -= nxt_r - val_r;
            else smaller -= val_r - nxt_r;
        }

        bit.upd(l, x);
        bit.upd(r + 1, -x);

        val_l = bit.get(l);
        pre_l = bit.get(l - 1);
        if(val_l > pre_l) larger += val_l - pre_l;
        else smaller += pre_l - val_l;

        val_r = bit.get(r);
        nxt_r = bit.get(r + 1);
        if(r < N){
            if(nxt_r > val_r) larger += nxt_r - val_r;
            else smaller += val_r - nxt_r;
        }

        cout << -1LL * larger * S + 1LL * smaller * T << '\n';
    }
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
//     freopen("bdbang.inp","r",stdin);
//     freopen("bdbang.out","w",stdout);

    int t = 1;
//    cin >> t;
    while(t--)
        solve();

    return 0;
}

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