이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include <bits/stdc++.h>
using i64 = long long;
struct line {
i64 a, b;
line(i64 _a, i64 _b) : a(_a), b(_b) {}
long double intersect(line rhs) {
return (long double)(b - rhs.b) / (rhs.a - a);
}
i64 eval(i64 x) {
return a * x + b;
}
bool operator== (line rhs) {
return a == rhs.a && b == rhs.b;
}
};
long double intersect(line a, line b, line c) {
return (a.b - b.b) * (c.a - b.a) >= (b.b - c.b) * (b.a - a.a);
}
namespace std {
std::string to_string(line l) {
return '(' + to_string(l.a) + "x + " + to_string(l.b) + ')';
}
};
#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) void(23)
#endif
constexpr int maxN = 1E5 + 5;
constexpr int maxK = 200 + 5;
int A[maxN], go[maxK][maxN];
i64 dp[maxK][maxN], p[maxN];
signed main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int N, K;
std::cin >> N >> K;
for(int i = 1; i <= N; i++) {
std::cin >> A[i];
}
for(int i = 1; i <= N; i++) {
p[i] = p[i - 1] + A[i];
}
std::deque<std::pair<line, int>> dq;
auto size = [&]() -> int { return (int) dq.size(); };
auto Add = [&](line l, int idx) -> void {
while(size() >= 2 && (l == dq[0].first || intersect(l, dq[0].first, dq[1].first))) {
dq.pop_front();
}
if(size() && l == dq[0].first) {
dq.pop_front();
}
dq.emplace_front(l, idx);
};
auto Query = [&](i64 x) -> std::pair<i64, int> {
int l = 0, r = size() - 1;
while(r - l > 3) {
int m = (l + r) >> 1;
if(dq[m].first.eval(x) < dq[m + 1].first.eval(x)) {
l = m + 1;
} else {
r = m;
}
}
auto ans = std::pair{dq[l].first.eval(x), dq[l].second};
for(int i = l; i <= r; i++) {
ans = std::max(ans, std::pair{dq[i].first.eval(x), dq[i].second});
}
return ans;
};
for(int k = 1; k <= K; k++) {
dq.clear();
Add({0, 0}, 0);
for(int i = 1; i <= N; i++) {
// for(int j = 0; j < i; j++) {
// if(dp[k - 1][j] + 1LL * (p[i] - p[j]) * (p[N] - p[i]) >= dp[k][i]) {
// go[k][i] = j;
// dp[k][i] = dp[k - 1][j] + 1LL * (p[i] - p[j]) * (p[N] - p[i]);
// }
// }
auto [v, j] = Query(p[N] - p[i]);
dp[k][i] = v + 1LL * p[i] * (p[N] - p[i]);
go[k][i] = j;
Add(line{-p[i], dp[k - 1][i]}, i);
debug(dq);
debug(k, i, dp[k][i], go[k][i]);
}
}
int ans = 1;
for(int i = 1; i < N; i++) {
if(dp[K][i] >= dp[K][ans]) {
ans = i;
}
}
std::cout << dp[K][ans] << '\n';
std::vector<int> v;
for(int k = K; k >= 1; k--) {
v.emplace_back(ans);
ans = go[k][ans];
}
for(int i = K - 1; i >= 0; i--) {
std::cout << v[i] << " \n"[i == 0];
}
return 0;
}
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