Submission #267323

#	Time	Username	Problem	Language	Result	Execution time	Memory
267323		leductoan	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	496 ms	13944 KiB

foehn_phenomena

#include<bits/stdc++.h>
using namespace std;
#define task "Phenomena"
#define lb lower_bound
#define ub upper_bound
#define alll(v) (v).begin(),(v).end()
#define szz(v) (v).size()
#define fi first
#define se second
#define pb push_back
#define FOR(i,a,b) for (ll i = (a), _b = (b); i <= _b; ++i)
#define FORD(i,b,a) for (ll i = (b), _a = (a); i >= _a; --i)
typedef long double ld;
typedef long long ll;
typedef pair<ll,ll> pii;

const ll MOD=1000000007; /// 998244353
const ll base=311; /// for hash actually
const ll N=2e5+5;

ll st[4*N],lazy[4*N],n,q,s,t,a[N];
void down(ll i, ll l, ll r)
{
    ll t=lazy[i];
    st[i<<1]+=t;
    st[i<<1|1]+=t;
    lazy[i<<1]+=t;
    lazy[i<<1|1]+=t;
    lazy[i]=0;
}
void upd(ll i, ll l, ll r, ll u, ll v, ll val)
{
    if(u>r||v<l) return;
    if(u<=l&&r<=v)
    {
        lazy[i]+=val;
        st[i]+=val;
        return;
    }
    down(i,l,r);
    ll mid=(l+r)>>1;
    upd(i<<1,l,mid,u,v,val);
    upd(i<<1|1,mid+1,r,u,v,val);
}
ll get(ll i, ll l, ll r, ll p)
{
    if(l==r) return st[i];
    down(i,l,r);
    ll mid=(l+r)>>1;
    if(p<=mid) return get(i<<1,l,mid,p);
    else return get(i<<1|1,mid+1,r,p);
}
void solved()
{
    cin>>n>>q>>s>>t;
    s=-s;
    ll ans=0;
    ++n;
    FOR(i,1,n)
    {
        cin>>a[i];
        upd(1,1,n,i,i,a[i]);
    }
    FOR(i,1,n-1)
    {
        if(a[i]<a[i+1]) ans+=s*(a[i+1]-a[i]);
        else ans+=t*(a[i]-a[i+1]);
    }
    while(q--)
    {
        ll l,r,x;
        cin>>l>>r>>x;
        ++l,++r;
        ll p1=get(1,1,n,l-1), p2=get(1,1,n,l);
        if(l>1&&p1<p2) ans-=s*(p2-p1);
        else ans-=t*(p1-p2);
//        cout<<s*(p2-p1)<<endl;s
        p1=get(1,1,n,r), p2=get(1,1,n,r+1);
        if(r<n&&p1<p2) ans-=s*(p2-p1);
        else ans-=t*(p1-p2);
//        cout<<ans<<endl;
        upd(1,1,n,l,r,x);
        p1=get(1,1,n,l-1), p2=get(1,1,n,l);
        if(l>1&&p1<p2) ans+=s*(p2-p1);
        else ans+=t*(p1-p2);
        p1=get(1,1,n,r), p2=get(1,1,n,r+1);
        if(r<n&&p1<p2) ans+=s*(p2-p1);
        else ans+=t*(p1-p2);
        cout<<ans<<'\n';
        /*FOR(i,1,n) cout<<get(1,1,n,i)<<' ';
        cout<<endl;*/
    }
}
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    if(fopen(task".inp","r"))
    {
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    solved();
}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int main()':
foehn_phenomena.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   99 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foehn_phenomena.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  100 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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