#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define int long long
const int64_t INF = 1 << 30;
const int N = 1e5 + 5;
const int LG = 17;
int dp[N][LG][LG], mn[N][LG], a[N], n, lg, cp[N];
/*
int solve(int x) {
int tx = x, cur = 0, ans = 0;
FOR(i, 0, LG) if (tx >> i & 1) {
ans += dp[cur][i][0];
cur += 1 << i;
}
tx = n - x, cur = n;
FOR(i, 0, LG) if (tx >> i & 1) {
cur -= 1 << i;
ans += dp[cur][i][0];
}
return ans;
}
*/
void add(int l, int r) {
while (l < r) cp[l++]--;
}
int solve(int x) {
copy(a, a + n, cp);
int ans = 0;
for (int i = LG - 1; i >= 0; i--) {
int tx = x;
while (tx < n) {
int m = *min_element(cp + tx, cp + tx + (1 << i));
if (m >= 1) add(tx, tx + (1 << i)), ans++;
tx += 1 << i;
}
if (x >> i & 1) x ^= 1 << i;
}
int m = *max_element(cp, cp + n);
return (m == 0 ? ans : INF);
}
signed main() {
ios::sync_with_stdio(0), cin.tie(0);
cin >> n;
FOR(i, 0, n) cin >> a[i];
for (int x = n - 1; x >= 0; x--) {
mn[x][0] = a[x];
for (int i = 1; (1 << i) + x <= n; i++)
mn[x][i] = min(mn[x][i - 1], mn[x + (1 << (i - 1))][i - 1]);
FOR(j, 0, LG) {
if (a[x] <= j + 1) dp[x][0][j] = (a[x] == j + 1);
else dp[x][0][j] = INF;
}
for (int i = 1; (1 << i) + x <= n; i++) {
FOR(j, 0, LG) {
dp[x][i][j] = dp[x][i - 1][j] + dp[x + (1 << (i - 1))][i - 1][j];
if (mn[x][i] > j)
dp[x][i][j] = min(dp[x][i][j], dp[x][i - 1][j + 1] + dp[x + (1 << (i - 1))][i - 1][j + 1] + 1);
}
}
}
int ans = INF;
FOR(i, 0, n) {
ans = min(ans, solve(i));
}
if (ans >= INF) ans = -1;
cout << ans << '\n';
}
//10:39:29
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
76 ms |
1748 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
76 ms |
1748 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
