1 files changed, 92 insertions, 0 deletions
diff --git a/test/string/rollingHash.cpp b/test/string/rollingHash.cpp
new file mode 100644
index 0000000..0491bc0
--- /dev/null
+++ b/test/string/rollingHash.cpp
@@ -0,0 +1,92 @@
+#include "../util.h"
+#include <string/rollingHash.cpp>
+
+string thueMorse(ll n) {
+	string res = "a";
+	while (sz(res) < n) {
+		string tmp = res;
+		for (char& c : tmp) c ^= 1;
+		res += tmp;
+	}
+	return res;
+}
+
+auto getHash(const string& s) {
+	return Hash(s)(0, sz(s));
+}
+
+void testThueMorse() {
+	set<decltype(getHash(""))> got;
+	set<string> expected;
+	string s = thueMorse(1000);
+	Hash h(s);
+	for (int l = 0; l < sz(s); l++) {
+		for (int r = l + 1; r <= sz(s); r++) {
+			got.insert(h(l, r));
+			expected.insert(s.substr(l, r - l));
+		}
+	}
+	if (sz(got) != sz(expected)) cerr << "error: thueMorse" << FAIL;
+	cerr << "thueMorse: ok" << endl;
+}
+
+void testTiny() {
+	if (getHash("aa") == getHash("a")) cerr << "error: tiny" << FAIL;
+	if (getHash("00") == getHash("0")) cerr << "error: tiny" << FAIL;
+	if (getHash("AA") == getHash("A")) cerr << "error: tiny" << FAIL;
+	cerr << "tiny: ok" << endl;
+}
+
+void testSmall() {
+	set<decltype(getHash(""))> got;
+	ll expected = 0;
+	auto dfs = [&](auto&& self, string pref)->void {
+		expected++;
+		got.insert(getHash(pref));
+		if(sz(pref) >= 5) return;
+		for (char c = 'a'; c <= 'z'; c++) {
+			self(self, pref + c);
+		}
+	};
+	dfs(dfs, "");
+	if (sz(got) != expected) cerr << "error: small" << FAIL;
+	cerr << "small: ok" << endl;
+}
+
+void stress_test() {
+	set<decltype(getHash(""))> got;
+	set<string> expected;
+	string s = Random::string(1000, "abc");
+	Hash h(s);
+	for (int l = 0; l < sz(s); l++) {
+		for (int r = l + 1; r <= sz(s); r++) {
+			got.insert(h(l, r));
+			expected.insert(s.substr(l, r - l));
+		}
+	}
+	if (sz(got) != sz(expected)) cerr << "error: stress test" << FAIL;
+	cerr << "stress test: ok" << endl;
+}
+
+constexpr int N = 1'000'000;
+void performance_test() {
+	timer t;
+	auto s = Random::string(N, "a") + Random::string(N, "ab") + Random::string(N, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789$#");
+	hash_t hash = 0;
+	t.start();
+	Hash h(s);
+	for (ll i = 0; i < N; i++) {
+		hash += h(i, i + 2*N);
+	}
+	t.stop();
+	if (t.time > 500) cerr << "too slow: " << t.time << FAIL;
+	cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
+}
+
+int main() {
+	testThueMorse();
+	testTiny();
+	testSmall();
+	stress_test();
+	performance_test();
+}