//Author: Kevin
#include<bits/stdc++.h>
//#pragma GCC optimize("O2")
using namespace std;
#define pb emplace_back
#define mp make_pair
#define ALL(x) (x).begin(),(x).end()
#define rALL(x) (x).rbegin(),(x).rend()
#define srt(x) sort(ALL(x))
#define rev(x) reverse(ALL(x))
#define rsrt(x) sort(rALL(x))
#define sz(x) (int)(x.size())
#define inf 0x3f3f3f3f
#define lb(v,x) (int)(lower_bound(ALL(v),x)-v.begin())
#define ub(v,x) (int)(upper_bound(ALL(v),x)-v.begin())
#define uni(v) v.resize(unique(ALL(v))-v.begin())
using ll=long long;
using ull=unsigned long long;
using pii=pair<int,int>;
using i128=__int128_t;
void die(string S){puts(S.c_str());exit(0);}
int n;
int a[2002000];
int d[2002000];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin>>n;
for(int i=1;i<=n;i++)
{
cin>>a[i];
a[n+i]=a[i];
}
vector<int> st;
st.pb(0);
for(int i=1;i<=n*2;i++)
{
while(sz(st)>1&&a[st.back()]<a[i]) st.pop_back();
d[st.back()+1]++;
d[i+1]--;
st.pb(i);
}
for(int i=1;i<=n*2;i++)
d[i]+=d[i-1];
cout<<*max_element(d,d+n*2+1)<<'\n';
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | //Author: Kevin #include<bits/stdc++.h> //#pragma GCC optimize("O2") using namespace std; #define pb emplace_back #define mp make_pair #define ALL(x) (x).begin(),(x).end() #define rALL(x) (x).rbegin(),(x).rend() #define srt(x) sort(ALL(x)) #define rev(x) reverse(ALL(x)) #define rsrt(x) sort(rALL(x)) #define sz(x) (int)(x.size()) #define inf 0x3f3f3f3f #define lb(v,x) (int)(lower_bound(ALL(v),x)-v.begin()) #define ub(v,x) (int)(upper_bound(ALL(v),x)-v.begin()) #define uni(v) v.resize(unique(ALL(v))-v.begin()) using ll=long long; using ull=unsigned long long; using pii=pair<int,int>; using i128=__int128_t; void die(string S){puts(S.c_str());exit(0);} int n; int a[2002000]; int d[2002000]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin>>n; for(int i=1;i<=n;i++) { cin>>a[i]; a[n+i]=a[i]; } vector<int> st; st.pb(0); for(int i=1;i<=n*2;i++) { while(sz(st)>1&&a[st.back()]<a[i]) st.pop_back(); d[st.back()+1]++; d[i+1]--; st.pb(i); } for(int i=1;i<=n*2;i++) d[i]+=d[i-1]; cout<<*max_element(d,d+n*2+1)<<'\n'; return 0; } |
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