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#include "../util.h"
#include <string/longestCommonSubsequence.cpp>
bool isSubstr(string_view s, string_view sub) {
int i = 0;
for (char c : s) {
if (i < ssize(sub) && c == sub[i]) i++;
}
return i >= ssize(sub);
}
string naive(string_view s, string_view t) {
string res = "";
for (ll i = 1; i < (1ll << ssize(s)); i++) {
string tmp;
for (ll j = 0; j < ssize(s); j++) {
if (((i >> j) & 1) != 0) tmp.push_back(s[j]);
}
if (ssize(tmp) >= ssize(res) && isSubstr(t, tmp)) res = tmp;
}
return res;
}
void stress_test() {
ll queries = 0;
for (ll i = 0; i < 10'000; i++) {
int n = Random::integer<int>(1, 12);
int m = Random::integer<int>(1, 12);
auto s = Random::string(n, "abc");
auto t = Random::string(m, "abc");
auto got = lcss(s, t);
auto expected = naive(s, t);
if (got != expected) cerr << s << ", " << t << ", got: " << got << ", expected: " << expected << FAIL;
queries += n + m;
}
cerr << "tested random queries: " << queries << endl;
}
constexpr int N = 2'000;
void performance_test() {
timer t;
auto a = Random::string(N, "a") + Random::string(N, "ab") + Random::string(N, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789$#");
auto b = Random::string(N, "a") + Random::string(N, "ab") + Random::string(N, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789$#");
t.start();
auto res = lcss(a, b);
t.stop();
hash_t hash = ssize(res);
if (t.time > 500) cerr << "too slow: " << t.time << FAIL;
cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
}
int main() {
stress_test();
performance_test();
}
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