| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 625475 | I_love_Hoang_Yen | Distributing Candies (IOI21_candies) | 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.
#include "bits/stdc++.h"
using namespace std;
using Query = std::tuple<int,int,int>;
// Lazy Segment Tree, copied from AtCoder {{{
// Source: https://github.com/atcoder/ac-library/blob/master/atcoder/lazysegtree.hpp
// Doc: https://atcoder.github.io/ac-library/master/document_en/lazysegtree.html
//
// Notes:
// - Index of elements from 0
// - Range queries are [l, r-1]
// - composition(f, g) should return f(g())
//
// Tested:
// - https://oj.vnoi.info/problem/qmax2
// - https://oj.vnoi.info/problem/lites
// - (range set, add, mult, sum) https://oj.vnoi.info/problem/segtree_itmix
// - (range add (i-L)*A + B, sum) https://oj.vnoi.info/problem/segtree_itladder
// - https://atcoder.jp/contests/practice2/tasks/practice2_l
// - https://judge.yosupo.jp/problem/range_affine_range_sum
int ceil_pow2(int n) {
int x = 0;
while ((1U << x) < (unsigned int)(n)) x++;
return x;
}
template<
class S, // node data type
S (*op) (S, S), // combine 2 nodes
S (*e) (), // identity element
class F, // lazy propagation tag
S (*mapping) (F, S), // apply tag F on a node
F (*composition) (F, F), // combine 2 tags
F (*id)() // identity tag
>
struct LazySegTree {
LazySegTree() : LazySegTree(0) {}
explicit LazySegTree(int n) : LazySegTree(vector<S>(n, e())) {}
explicit LazySegTree(const vector<S>& v) : _n((int) v.size()) {
log = ceil_pow2(_n);
size = 1 << log;
d = std::vector<S>(2 * size, e());
lz = std::vector<F>(size, id());
for (int i = 0; i < _n; i++) d[size + i] = v[i];
for (int i = size - 1; i >= 1; i--) {
update(i);
}
}
// 0 <= p < n
void set(int p, S x) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
d[p] = x;
for (int i = 1; i <= log; i++) update(p >> i);
}
// 0 <= p < n
S get(int p) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
return d[p];
}
// Get product in range [l, r-1]
// 0 <= l <= r <= n
// For empty segment (l == r) -> return e()
S prod(int l, int r) {
assert(0 <= l && l <= r && r <= _n);
if (l == r) return e();
l += size;
r += size;
for (int i = log; i >= 1; i--) {
if (((l >> i) << i) != l) push(l >> i);
if (((r >> i) << i) != r) push((r - 1) >> i);
}
S sml = e(), smr = e();
while (l < r) {
if (l & 1) sml = op(sml, d[l++]);
if (r & 1) smr = op(d[--r], smr);
l >>= 1;
r >>= 1;
}
return op(sml, smr);
}
S all_prod() {
return d[1];
}
// 0 <= p < n
void apply(int p, F f) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
d[p] = mapping(f, d[p]);
for (int i = 1; i <= log; i++) update(p >> i);
}
// Apply f on all elements in range [l, r-1]
// 0 <= l <= r <= n
void apply(int l, int r, F f) {
assert(0 <= l && l <= r && r <= _n);
if (l == r) return;
l += size;
r += size;
for (int i = log; i >= 1; i--) {
if (((l >> i) << i) != l) push(l >> i);
if (((r >> i) << i) != r) push((r - 1) >> i);
}
{
int l2 = l, r2 = r;
while (l < r) {
if (l & 1) all_apply(l++, f);
if (r & 1) all_apply(--r, f);
l >>= 1;
r >>= 1;
}
l = l2;
r = r2;
}
for (int i = 1; i <= log; i++) {
if (((l >> i) << i) != l) update(l >> i);
if (((r >> i) << i) != r) update((r - 1) >> i);
}
}
// Binary search on SegTree to find largest r:
// f(op(a[l] .. a[r-1])) = true (assuming empty array is always true)
// f(op(a[l] .. a[r])) = false (assuming op(..., a[n]), which is out of bound, is always false)
template <bool (*g)(S)> int max_right(int l) {
return max_right(l, [](S x) { return g(x); });
}
template <class G> int max_right(int l, G g) {
assert(0 <= l && l <= _n);
assert(g(e()));
if (l == _n) return _n;
l += size;
for (int i = log; i >= 1; i--) push(l >> i);
S sm = e();
do {
while (l % 2 == 0) l >>= 1;
if (!g(op(sm, d[l]))) {
while (l < size) {
push(l);
l = (2 * l);
if (g(op(sm, d[l]))) {
sm = op(sm, d[l]);
l++;
}
}
return l - size;
}
sm = op(sm, d[l]);
l++;
} while ((l & -l) != l);
return _n;
}
// Binary search on SegTree to find smallest l:
// f(op(a[l] .. a[r-1])) = true (assuming empty array is always true)
// f(op(a[l-1] .. a[r-1])) = false (assuming op(a[-1], ..), which is out of bound, is always false)
template <bool (*g)(S)> int min_left(int r) {
return min_left(r, [](S x) { return g(x); });
}
template <class G> int min_left(int r, G g) {
assert(0 <= r && r <= _n);
assert(g(e()));
if (r == 0) return 0;
r += size;
for (int i = log; i >= 1; i--) push((r - 1) >> i);
S sm = e();
do {
r--;
while (r > 1 && (r % 2)) r >>= 1;
if (!g(op(d[r], sm))) {
while (r < size) {
push(r);
r = (2 * r + 1);
if (g(op(d[r], sm))) {
sm = op(d[r], sm);
r--;
}
}
return r + 1 - size;
}
sm = op(d[r], sm);
} while ((r & -r) != r);
return 0;
}
private:
int _n, size, log;
vector<S> d;
vector<F> lz;
void update(int k) {
d[k] = op(d[2*k], d[2*k+1]);
}
void all_apply(int k, F f) {
d[k] = mapping(f, d[k]);
if (k < size) lz[k] = composition(f, lz[k]);
}
void push(int k) {
all_apply(2*k, lz[k]);
all_apply(2*k+1, lz[k]);
lz[k] = id();
}
};
// }}}
const long long INF = static_cast<long long> (2e18);
struct S { long long suf_min, suf_max; };
S op(S left, S right) {
return S {
std::min(left.suf_min, right.suf_min),
std::max(left.suf_max, right.suf_max),
};
};
S e() { return S{ INF, -INF }; }
S mapping(long long f, S s) { return S{ f + s.suf_min, f + s.suf_max }; }
long long composition(long long f, long long g) { return f + g; }
long long id() { return 0; }
std::vector<int> sub5(
const std::vector<int>& c,
const std::vector<Query>& queries) {
std::vector< std::vector< std::pair<int, long long> > > addAt(c.size()), removeAt(c.size());
for (int i = 0; i < (int) queries.size(); ++i) {
auto [l, r, v] = queries[i];
addAt[l].push_back({i, v});
removeAt[r].push_back({i, -v});
}
int q = queries.size();
LazySegTree<S, op, e, long long, mapping, composition, id> st(std::vector<S> (q+1, {0, 0}));
std::vector<int> a(c.size());
for (int i = 0; i < (int) a.size(); ++i) {
for (auto [queryId, val] : addAt[i]) {
st.apply(queryId + 1, q + 1, val);
}
auto suffix_max = [&] (int i) {
return st.prod(i, q + 1).suf_max;
};
auto suffix_min = [&] (int i) {
return st.prod(i, q + 1).suf_min;
};
auto sum_v = [&] (int i) {
return st.get(i).suf_min;
};
// find last index t where suffix_max(t) - suffix_min(t) > c[i]
auto r = std::views::iota(0, q + 1);
auto res = std::ranges::partition_point(
r,
[&] (int mid) {
return suffix_max(mid) - suffix_min(mid) > c[i];
});
if (res == r.begin()) a[i] = sum_v(q) - suffix_min(0);
else {
--res;
if (sum_v(*res) < sum_v(q)) {
// currently touch lower bar, then finally touch upper bar once
// after touching upper bar:
// - upper bar will finally be at suffix_max[*res]
// - final distance to upper bar is suffix_max[*res] - sum_vs
a[i] = c[i] - (suffix_max(*res) - sum_v(q));
} else {
a[i] = sum_v(q) - suffix_min(*res);
}
}
for (auto [queryId, val] : removeAt[i]) {
st.apply(queryId + 1, q + 1, val);
}
}
return a;
}
std::vector<int> distribute_candies(
std::vector<int> c,
std::vector<int> l,
std::vector<int> r,
std::vector<int> v) {
int q = (int) l.size();
std::vector<Query> queries;
for (int i = 0; i < q; ++i) {
queries.push_back({l[i], r[i], v[i]});
}
return sub5(c, queries);
}