Submission #926881

#	Time	Username	Problem	Language	Result	Execution time	Memory
926881		haru09	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	111 ms	12560 KiB

foehn_phenomena

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define task "code"

const int ar=2e5+5;
const ll mod=1e9+7;
int n,q,s,t;
int a[ar];
ll ans=0;
ll bit[ar];
void update(int u,int v)
{
    int id=u;
    while(id<=n+1)
    {
        bit[id]+=v;
        id+=id&(-id);
    }
}
ll get(int p)
{
    int id=p;
    ll ans=0;
    while(id>0)
    {
        ans+=bit[id];
        id-=id&(-id);
    }
    return ans;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    if (fopen(task".inp","r"))
    {
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    cin>>n>>q>>s>>t;
    for (int i=0;i<=n;i++)
    {
        cin>>a[i];
        if (i) update(i,a[i]),update(i+1,-a[i]);
    }
    for (int i=1;i<=n;i++)
    {
        if (a[i]>a[i-1]) ans-=1ll*s*(a[i]-a[i-1]);
        else ans+=1ll*t*(a[i-1]-a[i]);
    }
    while(q--)
    {
        int l,r,x;
        ll val1,val2;
        cin>>l>>r>>x;
        val1=get(l);
        val2=get(l-1);
        if (val1>val2) ans+=(val1-val2)*s;
        else ans-=(val2-val1)*t;
        if (r<n)
        {
            val1=get(r+1);
            val2=get(r);
            if (val1>val2) ans+=(val1-val2)*s;
            else ans-=(val2-val1)*t;
        }
        update(l,x);
        update(r+1,-x);

        val1=get(l);
        val2=get(l-1);
        if (val1>val2) ans-=(val1-val2)*s;
        else ans+=(val2-val1)*t;
        if (r<n)
        {
            val1=get(r+1);
            val2=get(r);
            if (val1>val2) ans-=(val1-val2)*s;
            else ans+=(val2-val1)*t;
        }

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

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int main()':
foehn_phenomena.cpp:40:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foehn_phenomena.cpp:41:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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