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#include "../../util.h"
#include <math/modPowIterativ.cpp>
#include <math/transforms/fft.cpp>
#pragma GCC diagnostic ignored "-Wnarrowing"
#include <math/transforms/fftMul.cpp>
vector<ll> from_cplx(const vector<cplx>& in) {
vector<ll> res(ssize(in));
for (int i = 0; i < ssize(in); i++) res[i] = llround(real(in[i]));
return res;
}
vector<ll> naive(const vector<ll>& a, const vector<ll>& b) {
vector<ll> res;
for (ll i = 1;; i *= 2) {
if (ssize(a) + ssize(b) <= i) {
res.resize(i, 0);
break;
}
}
for (int i = 0; i < ssize(a); i++) {
for (int j = 0; j < ssize(b); j++) {
res[i+j] += a[i] * b[j];
}
}
return res;
}
void stress_test() {
ll queries = 0;
for (ll i = 0; i < 10'000; i++) {
int n = Random::integer<int>(1, 100);
int m = Random::integer<int>(1, 100);
auto a = Random::integers<ll>(n, -1000, 1000);
auto b = Random::integers<ll>(m, -1000, 1000);
auto expected = naive(a, b);
auto got = from_cplx(mul(a, b));
if (got != expected) cerr << "error" << FAIL;
queries += n;
}
cerr << "tested queries: " << queries << endl;
}
constexpr int N = 1ll << 20;
void performance_test() {
timer t;
vector<ll> a = Random::integers<ll>(N, -1000, 1000);
vector<ll> b = Random::integers<ll>(N, -1000, 1000);
t.start();
auto got = from_cplx(mul(a, b));
t.stop();
hash_t hash = 0;
for (ll i = 0; i < N; i++) hash += i * got[i];
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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