#include "bits/stdc++.h"
using namespace std;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin >> n;
vector<int> pearls;
pearls.resize(2*n);
for(int i=0; i<n; i++) {
cin >> pearls[i];
pearls[n+i] = pearls[i];
}
vector<int> previous_higher;
previous_higher.resize(n*2);
vector<int> previous;
for(int i=0; i<n*2; i++) {
if(previous.empty()) {
previous_higher[i] = -1;
} else {
while(!previous.empty() && pearls[i] > pearls[previous.back()]) {
previous.pop_back();
}
if(previous.empty()) {
previous_higher[i] = -1;
} else {
previous_higher[i] = previous.back();
}
}
previous.push_back(i);
}
vector<int> count;
count.assign(n, 0);
int from, to;
for(int i=0; i<n*2; i++) {
from = previous_higher[i] + 1;
to = i;
if(from < i-n+1 ) {
from = i-n+1;
}
if(to > n-1) {
to = n-1;
}
if(from<=to) {
count[from]++;
count[to+1]--;
}
}
int result = 0;
int start_from = 0;
for(int i=0; i<n; i++) {
start_from += count[i];
if(start_from > result) {
result = start_from;
}
}
cout<<result<<"\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 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 | #include "bits/stdc++.h" using namespace std; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n; cin >> n; vector<int> pearls; pearls.resize(2*n); for(int i=0; i<n; i++) { cin >> pearls[i]; pearls[n+i] = pearls[i]; } vector<int> previous_higher; previous_higher.resize(n*2); vector<int> previous; for(int i=0; i<n*2; i++) { if(previous.empty()) { previous_higher[i] = -1; } else { while(!previous.empty() && pearls[i] > pearls[previous.back()]) { previous.pop_back(); } if(previous.empty()) { previous_higher[i] = -1; } else { previous_higher[i] = previous.back(); } } previous.push_back(i); } vector<int> count; count.assign(n, 0); int from, to; for(int i=0; i<n*2; i++) { from = previous_higher[i] + 1; to = i; if(from < i-n+1 ) { from = i-n+1; } if(to > n-1) { to = n-1; } if(from<=to) { count[from]++; count[to+1]--; } } int result = 0; int start_from = 0; for(int i=0; i<n; i++) { start_from += count[i]; if(start_from > result) { result = start_from; } } cout<<result<<"\n"; return 0; } |
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