#include <bits/stdc++.h>
#define MAX 500005
#define MOD (ll)(1e9+7)
#define INF (ll)(1e18)
#define inf (1987654321)
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
int n, q;
int arr[100005], ans[100005];
int L[100005][35], R[100005][35];
int l[100005][35], r[100005][35];
ll sum[100005];
vector<pair<pii, int> > event[100005];
struct INFO {
int l, r, i;
bool operator < (INFO q) {
if(r != q.r) return r < q.r;
else return pii(l, i) < pii(q.l, q.i);
}
} query[100005];
int seg[400005];
void update(int str, int ed, int idx, int val, int node) {
if(str == ed) {
seg[node] = val;
return;
}
int mid = str + ed >> 1;
if(idx <= mid) update(str, mid, idx, val, node << 1);
else update(mid + 1, ed, idx, val, node << 1 | 1);
seg[node] = max(seg[node << 1], seg[node << 1 | 1]);
}
int query1(int str, int ed, int x, int node) {
if(str == ed) return str;
int mid = str + ed >> 1;
if(seg[node << 1] > x) return query1(str, mid, x, node << 1);
else return query1(mid + 1, ed, x, node << 1 | 1);
}
int query2(int str, int ed, int x, int node) {
if(str == ed) return str;
int mid = str + ed >> 1;
if(seg[node << 1 | 1] > x) return query2(mid + 1, ed, x, node << 1 | 1);
else return query2(str, mid, x, node << 1);
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(NULL);
cin >> n;
for(int i = 1; i <= n; ++i) cin >> arr[i];
for(int i = 1; i <= n; ++i) sum[i] = sum[i - 1] + arr[i];
for(int i = 1, mx = 0; i <= n; ++i) {
L[i][0] = i;
for(int j = 1, x = arr[i]; x < mx; x <<= 1, ++j) L[i][j] = query2(1, n, x, 1);
update(1, n, i, arr[i], 1); mx = max(mx, arr[i]);
}
fill(seg + 1, seg + 4 * n + 1, 0);
for(int i = n, mx = 0; i >= 1; --i) {
R[i][0] = i;
for(int j = 1; j <= 30; ++j) R[i][j] = n + 1;
for(int j = 1, x = arr[i]; x < mx; x <<= 1, ++j) R[i][j] = query1(1, n, x, 1);
update(1, n, i, arr[i], 1); mx = max(mx, arr[i]);
}
arr[0] = arr[n + 1] = inf;
for(int i = 1; i <= n; ++i) {
l[i][0] = i;
for(int j = 1; j <= 30; ++j) {
if(R[i][j] == n + 1 || sum[R[i][j] - 1] - sum[L[i][j]] < (ll)min(arr[L[i][j]], arr[R[i][j]])) break;
int lo = 1, hi = i + 1;
while(lo + 1 < hi) {
int mid = lo + hi >> 1;
if(sum[R[i][j] - 1] - sum[mid - 1] >= arr[R[i][j]]) lo = mid;
else hi = mid;
}
l[i][j] = min(lo, l[i][j - 1]);
}
}
for(int i = 1; i <= n; ++i) {
r[i][0] = i;
for(int j = 1; j <= 30; ++j) r[i][j] = n + 1;
for(int j = 1; j <= 30; ++j) {
if(L[i][j] == 0 || sum[R[i][j] - 1] - sum[L[i][j]] < (ll)min(arr[L[i][j]], arr[R[i][j]])) break;
int lo = i - 1, hi = n;
while(lo + 1 < hi) {
int mid = lo + hi >> 1;
if(sum[mid] - sum[L[i][j]] >= arr[L[i][j]]) hi = mid;
else lo = mid;
}
r[i][j] = max(hi, r[i][j - 1]);
}
}
int ans = 0;
for(int i = 1; i <= n; ++i) {
int a = i - 1, b = n;
for(int j = 0; j <= 30; ++j) {
if(a > b) break;
if(R[i][j] != n + 1 && b > l[i][j]) b = l[i][j];
if(r[i][j] != n + 1 && a > L[i][j + 1]) a = L[i][j + 1];
}
//cout << a << ' ' << b << endl;
if(a < 1 && 1 <= b) ++ans;
}
cout << ans;
// for(int i = 1; i <= n; ++i) {
// cout << "r : " << i << endl;
// for(auto p : event[i]) cout << p.first.first << ' ' << p.first.second << ' ' << p.second << endl;
// cout << endl;
// }
//
// cin >> q;
// for(int i = 1; i <= q; ++i) {
// cin >> query[i].l >> query[i].r;
// query[i].i = i;
// }
// sort(query + 1, query + q + 1);
return 0;
}
Compilation message
fish2.cpp: In function 'void update(int, int, int, int, int)':
fish2.cpp:33:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
33 | int mid = str + ed >> 1;
| ~~~~^~~~
fish2.cpp: In function 'int query1(int, int, int, int)':
fish2.cpp:41:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
41 | int mid = str + ed >> 1;
| ~~~~^~~~
fish2.cpp: In function 'int query2(int, int, int, int)':
fish2.cpp:48:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
48 | int mid = str + ed >> 1;
| ~~~~^~~~
fish2.cpp: In function 'int main()':
fish2.cpp:82:30: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
82 | int mid = lo + hi >> 1;
| ~~~^~~~
fish2.cpp:97:30: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
97 | int mid = lo + hi >> 1;
| ~~~^~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
2 ms |
2692 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
2684 KB |
Output is correct |
| 2 |
Correct |
129 ms |
60680 KB |
Output is correct |
| 3 |
Correct |
171 ms |
60520 KB |
Output is correct |
| 4 |
Correct |
146 ms |
60760 KB |
Output is correct |
| 5 |
Correct |
171 ms |
60440 KB |
Output is correct |
| 6 |
Incorrect |
79 ms |
61144 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
2 ms |
2692 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
2684 KB |
Output is correct |
| 2 |
Correct |
129 ms |
60680 KB |
Output is correct |
| 3 |
Correct |
171 ms |
60520 KB |
Output is correct |
| 4 |
Correct |
146 ms |
60760 KB |
Output is correct |
| 5 |
Correct |
171 ms |
60440 KB |
Output is correct |
| 6 |
Incorrect |
79 ms |
61144 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
2684 KB |
Output is correct |
| 2 |
Correct |
129 ms |
60680 KB |
Output is correct |
| 3 |
Correct |
171 ms |
60520 KB |
Output is correct |
| 4 |
Correct |
146 ms |
60760 KB |
Output is correct |
| 5 |
Correct |
171 ms |
60440 KB |
Output is correct |
| 6 |
Incorrect |
79 ms |
61144 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
2 ms |
2692 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
