| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 541005 | mansur | Split the sequence (APIO14_sequence) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#include<bits/stdc++.h>
using namespace std;
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define sz(a) a.size()
//#define int long long
#define pb push_back
#define vt vector
#define s second
#define f first
#define nl '\n'
using pii = pair<int, int>;
using ll = long long;
vt<pii> dir = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
const int inf = 1e9, N = 1e6 + 5, mod = 1e9 + 7;
double eps = 1e-6;
bool fl = 0;
int ntr(pii a, pii b) {
int x = b.f - a.f;
int y = a.s - b.s;
return (x + y - 1) / y;
}
void solve() {
int n, k;
cin >> n >> k;
int p[n + 1];
bool is[n + 1][k + 1];
p[0] = 0;
for (int i = 1, a; i <= n; i++) {
cin >> a;
p[i] = p[i - 1] + a;
}
ll dp[n + 1][k + 1];
for (int i = 0; i <= n; i++) {
for (int s = 0; s <= k; s++) dp[i][s] = -inf, is[i][s] = 0;
}
dp[0][0] = 0;
vector<pair<pii, pii>> s;
s.pb({{-inf, -1}, {0, 0}});
for (int j = 0; j <= k; j++) {
int l = 0;
for (int i = j + 1; i <= n; i++) {
while (l < sz(s) && s[l].f.s < i && s[l].f.f <= p[i]) l++;
dp[i][j] = max(dp[i - 1][j], s[l - 1].s.f + s[l - 1].s.s * p[i]);
if (dp[i][j] == dp[i - 1][j]) {
is[i][j] = 1;
}
}
s.clear();
for (int i = j + 1; i <= n; i++) {
int a = dp[i][j] - p[i] * p[i], b = p[i];
int ps = -inf;
if (sz(s) && b == s.back().s.s) {
if (a > s.back().s.f) {
s.pop_back();
while (sz(s) && ntr({a, b}, s.back().s) <= s.back().f.f) s.pop_back();
if (sz(s)) ps = ntr({a, b}, s.back().s);
s.pb({{ps, i}, {a, b}});
}
continue;
}
while (sz(s) && ntr({a, b}, s.back().s) <= s.back().f.f) s.pop_back();
if (sz(s)) ps = ntr({a, b}, s.back().s);
s.pb({{ps, i}, {a, b}});
}
}
cout << dp[n][k] << nl;
vector<int> ans;
int i = n, j = k;
while (j > 0) {
if (is[i][j]) {
i--;
continue;
}
for (int x = j; x <= i - 1; x++) {
int a = dp[x][j - 1] - p[x] * p[x], b = p[x];
if (a + b * p[i] == dp[i][j]) {
i = x;
j--;
ans.pb(x);
break;
}
}
}
for (auto x: ans) cout << x << ' ';
}
main() {
//freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);
ios_base::sync_with_stdio(NULL);
cin.tie(NULL);
int tp = 1;
if (fl) cin >> tp;
while (tp--) solve();
}