#include<set>
#include<map>
#include<queue>
#include<vector>
#include<algorithm>
#include<bits/stdc++.h>
#define pr pair
#define f first
#define s second
#define ll long long
#define mp make_pair
#define pll pr<ll,ll>
#define pii pr<int,int>
#define piii pr<int,pii>
using namespace std;
int a[1000006];
int dp[1000006];
int main()
{
ios_base::sync_with_stdio(0);
int n;
cin>>n;
int mx=0;
for(int i=0;i<n;i++) cin>>a[i],mx=max(mx,a[i]);
int fd=-1;
for(int i=0;i<n;i++) if(a[i]==mx) fd=i;
rotate(a,a+fd+1,a+n);
vector<int> al;
int ans=0;
for(int i=0;i<n;i++)
{
while(al.size())
{
int g=al.back();
if(a[g]>=a[i]) break;
dp[i]=max(dp[i],dp[g]);
al.pop_back();
}
al.push_back(i);
dp[i]++;
ans=max(ans,dp[i]);
}
cout<<ans<<endl;
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 | #include<set> #include<map> #include<queue> #include<vector> #include<algorithm> #include<bits/stdc++.h> #define pr pair #define f first #define s second #define ll long long #define mp make_pair #define pll pr<ll,ll> #define pii pr<int,int> #define piii pr<int,pii> using namespace std; int a[1000006]; int dp[1000006]; int main() { ios_base::sync_with_stdio(0); int n; cin>>n; int mx=0; for(int i=0;i<n;i++) cin>>a[i],mx=max(mx,a[i]); int fd=-1; for(int i=0;i<n;i++) if(a[i]==mx) fd=i; rotate(a,a+fd+1,a+n); vector<int> al; int ans=0; for(int i=0;i<n;i++) { while(al.size()) { int g=al.back(); if(a[g]>=a[i]) break; dp[i]=max(dp[i],dp[g]); al.pop_back(); } al.push_back(i); dp[i]++; ans=max(ans,dp[i]); } cout<<ans<<endl; return 0; } |
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