Submission #534879

#	Time	Username	Problem	Language	Result	Execution time	Memory
534879		vector	Fancy Fence (CEOI20_fancyfence)	C++17	0 / 100	2 ms	460 KiB

fancyfence

#include<bits/stdc++.h>
#define MOD 1000000007
#define SIZE 100010
using namespace std;
typedef long long ll;
struct st2
{
    ll h,w,idx;
};
ll N,psum[SIZE],ans;
pair<ll,ll>seg[SIZE<<2];
st2 A[SIZE];
vector<st2>v;
void init(ll l,ll r,ll node)
{
    if(l==r){
        seg[node]={v[l].h,v[l].h};
        return;
    }
    ll mid=l+r>>1;
    init(l,mid,node<<1);
    init(mid+1,r,node<<1|1);
    seg[node]={max(seg[node<<1].first,seg[node<<1|1].first),min(seg[node<<1].second,seg[node<<1|1].second)};
}
pair<ll,ll>query(ll l,ll r,ll node,ll s,ll e)
{
    if(l>e||r<s||s>e)return {0,1e18};
    if(l==r)return seg[node];
    ll mid=l+r>>1;
    pair<ll,ll>p=query(l,mid,node<<1,s,e),q=query(mid+1,r,node<<1|1,s,e);
    return {max(p.first,q.first),min(p.second,q.second)};
}
ll S(ll x)
{
    return (x*(x+1)/2)%MOD;
}
int main()
{
    ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    cin>>N;
    for(int i=1;i<=N;i++)cin>>A[i].h;
    for(int i=1;i<=N;i++)cin>>A[i].w;
    bool f=false;
    st2 temp={0,0,0};
    v.push_back(temp);
    for(int i=1;i<=N;i++){
        if(f){
            if(temp.h==A[i].h)temp.w+=A[i].w;
            else{
                v.push_back(temp);
                f=false;
            }
        }
        if(!f){
            temp.h=A[i].h;
            temp.w=A[i].w;
            f=true;
        }
    }
    v.push_back(temp);
    N=v.size()-1;
    assert(N==1);
    for(int i=1;i<=N;i++){
        v[i].idx=i;
        //printf("[%lld %lld %lld]\n",v[i].h,v[i].w,v[i].idx);
        psum[i]=psum[i-1]+v[i].w;
    }
    init(1,N,1);
    for(int i=1;i<=N;i++){
        ll l=1,r=i,mid,a,b,c,d,mx=0;
        pair<ll,ll>t;
        while(l<r){
            mid=l+r>>1;
            t=query(1,N,1,mid,i);
            if(t.second>=v[i].h)r=mid;
            else l=mid+1;
        }
        a=r;
        l=i,r=N;
        while(l<r){
            mid=l+r+1>>1;
            t=query(1,N,1,i,mid);
            if(t.second>=v[i].h)l=mid;
            else r=mid-1;
        }
        b=l;
        l=1,r=i;
        while(l<r){
            mid=l+r>>1;
            t=query(1,N,1,mid,i);
            if(t.first<=v[i].h)r=mid;
            else l=mid+1;
        }
        c=r;
        l=i,r=N;
        while(l<r){
            mid=l+r+1>>1;
            t=query(1,N,1,i,mid);
            if(t.first<=v[i].h)l=mid;
            else r=mid-1;
        }
        d=l;
        mx=max(query(1,N,1,c,i-1).first,query(1,N,1,i+1,d).first);
        ans=(ans+S(psum[b]-psum[a-1])*(S(v[i].h)-S(mx)+MOD))%MOD;
    }
    cout<<ans;
}

Compilation message (stderr)

fancyfence.cpp: In function 'void init(ll, ll, ll)':
fancyfence.cpp:20:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   20 |     ll mid=l+r>>1;
      |            ~^~
fancyfence.cpp: In function 'std::pair<long long int, long long int> query(ll, ll, ll, ll, ll)':
fancyfence.cpp:29:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   29 |     ll mid=l+r>>1;
      |            ~^~
fancyfence.cpp: In function 'int main()':
fancyfence.cpp:73:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   73 |             mid=l+r>>1;
      |                 ~^~
fancyfence.cpp:81:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   81 |             mid=l+r+1>>1;
      |                 ~~~^~
fancyfence.cpp:89:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   89 |             mid=l+r>>1;
      |                 ~^~
fancyfence.cpp:97:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   97 |             mid=l+r+1>>1;
      |                 ~~~^~

• Subtask 1: 0 / 0
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27