#include <bits/stdc++.h>
using namespace std;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
cin >> n;
vector <int> a(n);
for (int i = 0; i < n; i++) {
cin >> a[i];
}
vector <int> prev(2*n);
vector <int> stack;
for (int i = 0; i < 2*n; i++) {
while (!stack.empty() && (a[stack.back()%n] < a[i%n] || stack.back() < i - n)) {
stack.pop_back();
}
if (stack.empty())
prev[i] = -1;
else
prev[i] = stack.back();
stack.push_back(i);
}
vector <int> intervals(2*n+1);
for (int i = 0; i < 2*n; i++) {
intervals[(prev[i]+1)]++;
intervals[i+1]--;
}
int res = 0;
int temp = 0;
for (int i = 0; i < 2*n; i++) {
temp += intervals[i];
res = max(res, temp);
}
cout << res << "\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 | #include <bits/stdc++.h> using namespace std; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); int n; cin >> n; vector <int> a(n); for (int i = 0; i < n; i++) { cin >> a[i]; } vector <int> prev(2*n); vector <int> stack; for (int i = 0; i < 2*n; i++) { while (!stack.empty() && (a[stack.back()%n] < a[i%n] || stack.back() < i - n)) { stack.pop_back(); } if (stack.empty()) prev[i] = -1; else prev[i] = stack.back(); stack.push_back(i); } vector <int> intervals(2*n+1); for (int i = 0; i < 2*n; i++) { intervals[(prev[i]+1)]++; intervals[i+1]--; } int res = 0; int temp = 0; for (int i = 0; i < 2*n; i++) { temp += intervals[i]; res = max(res, temp); } cout << res << "\n"; } |
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