//fast
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(n) for(int i = 0 ; i<n ; i++)
#define all(x) x.begin(),x.end()
#define pb push_back
const int base = (1<<20);
int tree[2*base];
void upd(int x, int c){
x+=base;
while (x>=1){
tree[x] = c;
x/=2;
}
}
int zap(int a, int b){
a+=base-1;
b+=base+1;
int w = 0;
while (b-a>1){
if (a%2==0) w = max(w,tree[a+1]);
if (b%2) w = max(w,tree[b-1]);
a/=2;
b/=2;
}
return w;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
int a[2*n];
rep(n) cin >> a[i+1];
rep(n-1) a[i+n+1] = a[i+1];
int w[2*n] = {0};
for (int i = 1 ; i<2*n ; i++){
w[zap(a[i],base-1)+1]++;
upd(a[i],i);
}
int sum = 0;
int maks = 0;
for (int i = 1 ; i<2*n ; i++){
sum+=w[i];
maks = max(maks,sum);
sum--;
}
cout << maks << '\n';
}
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 50 51 52 53 54 55 56 | //fast #include<bits/stdc++.h> using namespace std; typedef long long ll; typedef long double ld; #define rep(n) for(int i = 0 ; i<n ; i++) #define all(x) x.begin(),x.end() #define pb push_back const int base = (1<<20); int tree[2*base]; void upd(int x, int c){ x+=base; while (x>=1){ tree[x] = c; x/=2; } } int zap(int a, int b){ a+=base-1; b+=base+1; int w = 0; while (b-a>1){ if (a%2==0) w = max(w,tree[a+1]); if (b%2) w = max(w,tree[b-1]); a/=2; b/=2; } return w; } int main(){ ios_base::sync_with_stdio(0); cin.tie(0); int n; cin >> n; int a[2*n]; rep(n) cin >> a[i+1]; rep(n-1) a[i+n+1] = a[i+1]; int w[2*n] = {0}; for (int i = 1 ; i<2*n ; i++){ w[zap(a[i],base-1)+1]++; upd(a[i],i); } int sum = 0; int maks = 0; for (int i = 1 ; i<2*n ; i++){ sum+=w[i]; maks = max(maks,sum); sum--; } cout << maks << '\n'; } |
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