#include <bits/stdc++.h>
#include <cassert>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,fma")
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
#define MAX 1010101
#define MAXS 500
#define INF 1000000020
#define bb ' '
#define ln '\n'
#define Ln '\n'
struct node {
int mn;
int mn2;
int cnt;
int mnl, mnr;
node(int x = 0, int ind = 0) {
mnl = mnr = ind;
if (!~x) {
mn = mn2 = cnt = -1;
return;
}
mn = x;
mn2 = INF;
cnt = 1;
}
};
node operator+(node n1, node n2) {
if (!~n1.cnt) return n2;
if (!~n2.cnt) return n1;
node ret;
ret.mn = min(n1.mn, n2.mn);
ret.cnt = 0;
ret.mnl = INF;
ret.mnr = -INF;
if (ret.mn == n1.mn) ret.cnt += n1.cnt, ret.mnl = min(ret.mnl, n1.mnl), ret.mnr = max(ret.mnr, n1.mnr);
else ret.mn2 = min(ret.mn2, n1.mn);
if (ret.mn == n2.mn) ret.cnt += n2.cnt, ret.mnl = min(ret.mnl, n2.mnl), ret.mnr = max(ret.mnr, n2.mnr);
else ret.mn2 = min(ret.mn2, n2.mn);
ret.mn2 = min(ret.mn2, n1.mn2);
ret.mn2 = min(ret.mn2, n2.mn2);
return ret;
}
int N;
int H[MAX];
int ch[MAX];
namespace segtree {
int N;
node tree[MAX * 4];
int lazy[MAX * 4];
void init(int s, int e, int loc = 1) {
lazy[loc] = -1;
if (s == e) {
tree[loc] = node(H[s], s);
return;
}
int m = s + e >> 1;
init(s, m, loc * 2);
init(m + 1, e, loc * 2 + 1);
tree[loc] = tree[loc * 2] + tree[loc * 2 + 1];
}
void prop(int loc) {
for (auto c : { loc * 2, loc * 2 + 1 }) {
tree[c].mn = max(tree[c].mn, lazy[loc]);
lazy[c] = max(lazy[c], lazy[loc]);
assert(tree[c].mn < tree[c].mn2);
}
lazy[loc] = -1;
}
void upd(int s, int e, int l, int r, int v, int loc = 1) {
if (s != e) prop(loc);
if (e < l || r < s) return;
if (l <= s && e <= r) {
if (v < tree[loc].mn2) {
if (v > tree[loc].mn) {
tree[loc].mn = v;
lazy[loc] = max(lazy[loc], v);
}
return;
}
}
int m = s + e >> 1;
upd(s, m, l, r, v, loc * 2);
upd(m + 1, e, l, r, v, loc * 2 + 1);
tree[loc] = tree[loc * 2] + tree[loc * 2 + 1];
}
void upd(int low, int r, int v) { upd(1, N, low, r, v); }
node query(int s, int e, int l, int r, int loc = 1) {
if (s != e) prop(loc);
if (e < l || r < s) return node(-1);
if (l <= s && e <= r) return tree[loc];
int m = s + e >> 1;
return query(s, m, l, r, loc * 2) + query(m + 1, e, l, r, loc * 2 + 1);
}
node query(int l, int r) { return query(1, N, l, r); }
}
inline ll rsum(ll n) { return n * (n + 1) / 2; }
inline ll rsum(ll l, ll r) { return rsum(r) - rsum(l - 1); }
ll naive() {
int i, j;
ll ans = 0;
for (i = 1; i <= 100; i++) {
int l, r;
l = r = -1;
int cnt = 0;
for (j = 1; j <= N; j++) {
if (H[j] != i) continue;
if (ch[j] == H[j]) continue;
cnt++;
if (!~l) l = j;
r = j;
}
if (!cnt) continue;
if (l == r) {
ans += H[l - 1] + H[l] + H[l + 1];
H[l]++;
continue;
}
ans += H[l - 1] + H[r + 1] + min(H[l - 1], H[r + 1]);
ans += 1ll * i * cnt;
ans += 1ll * (2 * cnt - 3) * (i + 1);
for (j = l; j <= r; j++) if (H[j] == i) H[j]++;
}
return ans;
}
signed main() {
ios::sync_with_stdio(false), cin.tie(0);
cin >> N;
segtree::N = N;
int i;
for (i = 1; i <= N; i++) cin >> H[i];
ll ans = 0;
int mv = 1;
for (i = 1; i <= N; i++) if (H[mv] < H[i]) mv = i;
for (i = 1; i <= N; i++) ch[i] = H[i];
for (i = 1; i <= mv; i++) ch[i] = max(ch[i], ch[i - 1]);
for (i = N; i >= mv; i--) ch[i] = max(ch[i], ch[i + 1]);
for (i = 1; i <= N; i++) ans += rsum(H[i], ch[i] - 1);
cout << naive();
return 0;
segtree::init(1, N);
int low, high;
low = high = -1;
for (i = 1; i < N; i++) if (H[i] > H[i + 1]) {
low = i;
break;
}
if (!~low) {
cout << 0 << ln;
return 0;
}
for (i = N; i > 1; i--) if (H[i] > H[i - 1]) {
high = i;
break;
}
if (!~high) {
cout << 0 << ln;
return 0;
}
if (low >= high) {
cout << 0 << ln;
return 0;
}
set<int> lst, rst;
for (i = 1; i <= low; i++) lst.insert(H[i]);
for (i = high; i <= N; i++) rst.insert(H[i]);
while (low < high) {
while (low < N && segtree::query(low, low).mn <= segtree::query(low + 1, low + 1).mn) low++, lst.insert(H[low]);
while (high > 1 && segtree::query(high, high).mn <= segtree::query(high - 1, high - 1).mn) high--, rst.insert(H[high]);
if (low >= high) break;
auto res = segtree::query(low + 1, high - 1);
int mn = res.mn;
int n = res.cnt;
auto itl = lst.upper_bound(mn);
auto itr = rst.upper_bound(mn);
int up = min(res.mn2, min(*itl, *itr));
int ml = min(*itl, segtree::query(low, res.mnl).mn2);
int mr = min(*itr, segtree::query(res.mnr, high).mn2);
if (res.cnt == 1) {
ans += 1ll * (ml + mr) * (up - mn);
segtree::upd(low, high, up);
continue;
}
ans += rsum(mn + 1, up) * (n * 2 - 3);
ans += 1ll * (0ll + up + ml + mr) * (up - mn);
segtree::upd(low, high, up);
}
//cout << ans << ln;
cout << naive() << ln;
}
Compilation message
Main.cpp: In function 'void segtree::init(int, int, int)':
Main.cpp:62:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
62 | int m = s + e >> 1;
| ~~^~~
Main.cpp: In function 'void segtree::upd(int, int, int, int, int, int)':
Main.cpp:87:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
87 | int m = s + e >> 1;
| ~~^~~
Main.cpp: In function 'node segtree::query(int, int, int, int, int)':
Main.cpp:97:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
97 | int m = s + e >> 1;
| ~~^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
79348 KB |
Output is correct |
2 |
Correct |
30 ms |
79308 KB |
Output is correct |
3 |
Correct |
30 ms |
79288 KB |
Output is correct |
4 |
Incorrect |
31 ms |
79320 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |