Submission #654064

#	Time	Username	Problem	Language	Result	Execution time	Memory
654064		sofija6	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	187 ms	13120 KiB

foehn_phenomena

#include <bits/stdc++.h>
#define ll long long
#define MAXN 200010
using namespace std;
ll a[MAXN];
struct bit
{
    vector<ll> v;
    void Init()
    {
        v.resize(MAXN,0ll);
    }
    void Add(ll pos,ll val)
    {
        for (ll i=pos;i<MAXN;i+=i&(-i))
            v[i]+=val;
    }
    ll Calc(ll pos)
    {
        ll sum=0;
        for (ll i=pos;i>0;i-=i&(-i))
            sum+=v[i];
        return sum;
    }
    ll Query(ll l,ll r)
    {
        return Calc(r)-Calc(l-1);
    }
};
bit b;
int main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll n,q,s,t,ans=0,l,r,x;
    cin >> n >> q >> s >> t;
    for (ll i=0;i<=n;i++)
    {
        cin >> a[i];
        if (i)
        {
            if (a[i]>a[i-1])
                ans-=s*(a[i]-a[i-1]);
            else
                ans+=t*(a[i-1]-a[i]);
        }
    }
    b.Init();
    while (q--)
    {
        cin >> l >> r >> x;
        if (l)
        {
            ll val1=a[l-1]+b.Query(1,l-1),val2=a[l]+b.Query(1,l);
            if (val1<val2)
                ans+=s*(val2-val1);
            else
                ans-=t*(val1-val2);
        }
        r++;
        if (r<=n)
        {
            ll val1=a[r-1]+b.Query(1,r-1),val2=a[r]+b.Query(1,r);
            if (val1<val2)
                ans+=s*(val2-val1);
            else
                ans-=t*(val1-val2);
        }
        b.Add(l,x);
        b.Add(r,-x);
        if (l)
        {
            ll val1=a[l-1]+b.Query(1,l-1),val2=a[l]+b.Query(1,l);
            if (val1<val2)
                ans-=s*(val2-val1);
            else
                ans+=t*(val1-val2);
        }
        if (r<=n)
        {
            ll val1=a[r-1]+b.Query(1,r-1),val2=a[r]+b.Query(1,r);
            if (val1<val2)
                ans-=s*(val2-val1);
            else
                ans+=t*(val1-val2);
        }
        cout << ans << "\n";
    }
    return 0;
}

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