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feat: lev_dis & knapsack
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Tiphereth-A committed Mar 2, 2025
1 parent 2743d39 commit 9f682b5
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9 changes: 9 additions & 0 deletions config.yml
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Expand Up @@ -461,6 +461,9 @@ notebook:
- lis: 最长上升子序列
code_ext: hpp
test_ext: cpp
- lev_dis: Levenshtein 距离
code_ext: hpp
test_ext: cpp
- hoverline: 悬线法
code_ext: hpp
test_ext: cpp
Expand Down Expand Up @@ -488,9 +491,15 @@ notebook:
- simplex: 单纯形法
code_ext: hpp
test_ext: cpp
- knapsack_01: 01 背包
code_ext: hpp
test_ext: cpp
- knapsack_mixed: 混合背包
code_ext: hpp
test_ext: cpp
- knapsack_mixed_huge: 混合背包(贪心)
code_ext: hpp
test_ext: cpp
graph:
- alist: 邻接表
code_ext: hpp
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59 changes: 59 additions & 0 deletions src/code/opt/knapsack_01.hpp
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#ifndef TIFALIBS_OPT_KNAPSACK_01
#define TIFALIBS_OPT_KNAPSACK_01

#include "../util/traits.hpp"

namespace tifa_libs::opt {

//@param a a[i]={value, weight}
//@param W max weight
//@return max total value while total weight <= W
template <int_c T>
CEXP T knapsack_01(vecpt<T> CR a, T W) NE {
const T vs = [k = std::views::keys(a)] { return std::reduce(k.begin(), k.end(), T{}); }();
const T _1 = W, _2 = vs,
_3 = T(a.size() >= 128 ? -1_u64 : 1_u64 << ((a.size() + 1) / 2)),
_min = min({_1, _2, _3});
assert(0_isz <= (isz)_min && (usz)_min * a.size() < (usz)1e9);
if (_min == _1) {
vec<T> dp(W + 1);
for (auto [s, t] : a)
for (u32 j = u32(W - t); ~j; --j) dp[j + t] = max(dp[j + t], dp[j] + s);
return max(dp);
} else if (const T inf = to_uint_t<T>(-1) / 2 - 1; _min == _2) {
vec<T> dp(vs + 1, inf);
dp[0] = 0;
for (auto [s, t] : a)
for (u32 j = u32(vs - s); ~j; --j) dp[j + s] = min(dp[j + s], dp[j] + t);
T ans = 0;
flt_ (T, i, 0, T(vs + 1))
if (dp[i] <= W) ans = max(ans, i);
return ans;
} else {
auto f = [&](u32 l, u32 r) {
vecpt<T> res(1 << (r - l));
res[0] = {0, 0};
flt_ (u32, i, 0, r - l)
flt_ (u32, j, 0, 1 << i) {
auto&& [v, w] = a[l + i];
res[je + j] = {res[j].first + w, res[j].second + v};
}
sort(res);
flt_ (u32, i, 1, (u32)res.size()) res[i].second = max(res[i].second, res[i - 1].second);
return res;
};
auto l = f(0, (u32)a.size() / 2), r = f((u32)a.size() / 2, (u32)a.size());
reverse(l), r.emplace_back(inf, inf);
T ans = 0;
u32 id = -1_u32;
for (auto& [t, s] : l) {
while (t + r[id + 1].first <= W) ++id;
if (~id) ans = max(ans, s + r[id].second);
}
return ans;
}
}

} // namespace tifa_libs::opt

#endif
42 changes: 42 additions & 0 deletions src/code/opt/knapsack_mixed_huge.hpp
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#ifndef TIFALIBS_OPT_KNAPSACK_MIXED_HUGE
#define TIFALIBS_OPT_KNAPSACK_MIXED_HUGE

#include "../util/traits.hpp"

namespace tifa_libs::opt {

//@param a a[i]={value, weight, count}
//@param W max weight
//@return max total value while total weight <= W
template <int_c T>
CEXP T knapsack_mixed_huge(vec<pt3<T>> a, T W) NE {
const u32 n = (u32)a.size();
assert(n < 500);
const u32 lim = [k = max(n, 50_u32)] { return k * k * k + 1; }();
vec<T> dp(lim + 1, to_uint_t<T>(-1) / 2 - 1);
dp[0] = 0;
for (auto& [v, w, num] : a) {
T have = min(num, (T)n);
num -= have;
for (T k = 1; k = min(have, k), have; have -= k, k <<= 1)
for (u32 j = lim - 1; (T)j >= v * k; --j) dp[j] = min(dp[j], dp[j - v * k] + w * k);
}
vecu id(n);
std::iota(id.begin(), id.end(), 0), sort(id, [&](auto x, auto y) { return a[x]._0 * a[y]._1 > a[y]._0 * a[x]._1; });
T ans = 0;
flt_ (u32, j, 0, lim + 1) {
if (W < dp[j]) continue;
T rest = W - dp[j], now = j;
for (auto i : id) {
auto [v, w, num] = a[i];
T div = min(num, rest / w);
rest -= div * w, now += div * v;
}
ans = max(ans, now);
}
return ans;
}

} // namespace tifa_libs::opt

#endif
22 changes: 22 additions & 0 deletions src/code/opt/lev_dis.hpp
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#ifndef TIFALIBS_OPT_LEV_DIS
#define TIFALIBS_OPT_LEV_DIS

#include "../util/util.hpp"

namespace tifa_libs::opt {

//@return ans[i][j] = lev(a[0..i), b[0..j))
template <common_range T>
CEXP vvecu lev_dis(T CR a, T CR b) NE {
const u32 n = (u32)a.size(), m = (u32)b.size();
vvecu ans(n + 1, vecu(m + 1));
flt_ (u32, i, 0, n + 1) ans[i][0] = i;
flt_ (u32, i, 0, m + 1) ans[0][i] = i;
flt_ (u32, i, 1, n + 1)
flt_ (u32, j, 1, m + 1) ans[i][j] = min({ans[i - 1][j - 1] + !(a[i - 1] == b[j - 1]), ans[i][j - 1] + 1, ans[i - 1][j] + 1});
return ans;
}

} // namespace tifa_libs::opt

#endif
4 changes: 4 additions & 0 deletions src/doc_md/opt/knapsack_01.md
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---
title: knapsack_01
documentation_of: //src/code/opt/knapsack_01.hpp
---
4 changes: 4 additions & 0 deletions src/doc_md/opt/knapsack_mixed_huge.md
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---
title: knapsack_mixed_huge
documentation_of: //src/code/opt/knapsack_mixed_huge.hpp
---
4 changes: 4 additions & 0 deletions src/doc_md/opt/lev_dis.md
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---
title: lev_dis
documentation_of: //src/code/opt/lev_dis.hpp
---
1 change: 1 addition & 0 deletions src/doc_tex/opt/knapsack_01.tex
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\paragraph{复杂度} \(O\left(N\min\left\{W , \sum_i v_i , 2^{\frac{N}{2}}\right\}\right)\)
1 change: 1 addition & 0 deletions src/doc_tex/opt/knapsack_mixed_huge.tex
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适用于物品个数和价值均较小 (\(\leq 50\)) 且总容量较大 (\(10^9\)) 的情况
9 changes: 9 additions & 0 deletions src/doc_tex/opt/lev_dis.tex
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对两个序列 \(a\), \(b\), 其 Levenshtein 距离 \(\operatorname{lev}(a,b)\) 定义为通过对 \(a\) 进行 (插入, 删除, 修改) 单个元素使其变为 \(b\) 的最少操作次数. 令 \(a'\) 表示 \(a\) 删除第一个元素后的序列, 则

\[
\operatorname{lev}(a,b)=\begin{cases}
\max\{|a|,|b|\}, & |a|=0 ~\text{or}~ |b|=0, \\
\operatorname{lev}(a',b'), & a_0=b_0, \\
1+\min\{\operatorname{lev}(a',b),\operatorname{lev}(a,b'),\operatorname{lev}(a',b')\}, & \text{otherwise}.
\end{cases}
\]
13 changes: 13 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_b.knapsack_01.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_B"

#include "../../code/opt/knapsack_01.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
u32 n, w;
std::cin >> n >> w;
vecpt<u32> a(n);
for (auto& [v, w] : a) std::cin >> v >> w;
std::cout << tifa_libs::opt::knapsack_01(a, w) << '\n';
return 0;
}
11 changes: 11 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_e.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_E"

#include "../../code/opt/lev_dis.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
strn a, b;
std::cin >> a >> b;
std::cout << tifa_libs::opt::lev_dis(a, b).back().back() << '\n';
return 0;
}
13 changes: 13 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_f.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_F"

#include "../../code/opt/knapsack_01.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
u32 n, w;
std::cin >> n >> w;
vecpt<u32> a(n);
for (auto& [v, w] : a) std::cin >> v >> w;
std::cout << tifa_libs::opt::knapsack_01(a, w) << '\n';
return 0;
}
18 changes: 18 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_g.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_G"

#include "../../code/opt/knapsack_mixed.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
u32 n, w;
std::cin >> n >> w;
tifa_libs::opt::knapsack_mixed<i32> kn(w);
for (u32 i = 0; i < n; ++i) {
i32 v;
u32 w, m;
std::cin >> v >> w >> m;
kn.add(w, v, m);
}
std::cout << *std::ranges::max_element(kn.result()) << '\n';
return 0;
}
13 changes: 13 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_h.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_H"

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#include "../../code/opt/knapsack_01.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
u64 n, w;
std::cin >> n >> w;
vecpt<u64> a(n);
for (auto& [v, w] : a) std::cin >> v >> w;
std::cout << tifa_libs::opt::knapsack_01(a, w) << '\n';
return 0;
}
13 changes: 13 additions & 0 deletions src/test_cpverifier/aizu-dpl/dpl_1_i.test.cpp
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#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/7/DPL/all/DPL_1_I"

#include "../../code/opt/knapsack_mixed_huge.hpp"

int main() {
std::cin.tie(nullptr)->std::ios::sync_with_stdio(false);
u64 n, w;
std::cin >> n >> w;
vec<pt3uu> a(n);
for (auto& [v, w, num] : a) std::cin >> v >> w >> num;
std::cout << tifa_libs::opt::knapsack_mixed_huge(a, w) << '\n';
return 0;
}
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