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#include "../util.h"
#include <math/shortModInv.cpp>
#include <math/minMod.cpp>
ll naiveMinMod(ll n, ll m, ll a, ll b){
ll ans = m;
for(ll i = 0; i < n; i++){
ans = min(ans, (a*i+b)%m);
}
return ans;
}
ll naiveFirstVal(ll a, ll m, ll l, ll r){
for(ll i = 0; i < m; i++){
ll v = a*i % m;
if(l <= v && v <= r) return v;
}
return -1;
}
void stress_test_minMod() {
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);
int a = Random::integer<int>(0, m);
int b = Random::integer<int>(0, m);
ll expected = naiveMinMod(n, m, a, b);
ll got = minMod(n, m, a, b);
if (got != expected) cerr << "got: " << got << ", expected: " << expected << FAIL;
queries++;
}
cerr << "tested queries: " << queries << endl;
}
void stress_test_firstVal() {
ll queries = 0;
for (ll i = 0; i < 10'000; i++) {
int m = Random::integer<int>(1, 100);
int a = Random::integer<int>(0, m);
int l = Random::integer<int>(0, m);
int r = Random::integer<int>(0, m);
if(l > r) swap(l, r);
ll expected = naiveFirstVal(a, m, l, r);
ll got = firstVal(a, m, l, r);
if (got != expected) cerr << a << " " << m << " " << l << " " << r << "got: " << got << ", expected: " << expected << FAIL;
queries++;
}
cerr << "tested queries: " << queries << endl;
}
constexpr int N = 1'000'000;
void performance_test_minMod() {
timer t;
hash_t hash = 0;
for (int operations = 0; operations < N; operations++) {
ll n = Random::integer<ll>(1, 1'000'000'000);
ll m = Random::integer<ll>(1, 1'000'000'000);
ll a = Random::integer<ll>(0, m);
ll b = Random::integer<ll>(0, m);
t.start();
hash += minMod(n, m, a, b);
t.stop();
}
if (t.time > 750) cerr << "too slow: " << t.time << FAIL;
cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
}
void performance_test_firstVal() {
timer t;
hash_t hash = 0;
for (int operations = 0; operations < N; operations++) {
ll m = Random::integer<ll>(1, 1'000'000'000);
ll a = Random::integer<ll>(1, m);
ll l = Random::integer<ll>(0, m);
ll r = Random::integer<ll>(0, m);
if(l > r) swap(l, r);
t.start();
hash += firstVal(a, m, l, r);
t.stop();
}
if (t.time > 750) cerr << "too slow: " << t.time << FAIL;
cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
}
int main() {
stress_test_minMod();
stress_test_firstVal();
performance_test_minMod();
performance_test_firstVal();
}
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