diff --git a/unittest.cpp b/unittest.cpp
index 09e3f7a..f91aa73 100644
--- a/unittest.cpp
+++ b/unittest.cpp
@@ -10,3 +10,33 @@ TEST_CASE("distinct positive numbers") {
 	CHECK(min == 1);
 	CHECK(max == 2);
 }
+TEST_CASE("empty vector") {
+	double min = 0;
+	double max = 0;
+	find_minmax({NULL}, min, max);
+	CHECK(min == 0);
+	CHECK(max == 0);
+}
+TEST_CASE("one element") {
+	double min = 0;
+	double max = 0;
+	find_minmax({1}, min, max);
+	CHECK(min == 1);
+	CHECK(max == 1);
+}
+
+TEST_CASE("negative elements") {
+	double min = 0;
+	double max = 0;
+	find_minmax({-1, -2}, min, max);
+	CHECK(min == -2);
+	CHECK(max == -1);
+}
+TEST_CASE("same elements") {
+	double min = 0;
+	double max = 0;
+	find_minmax({1,1,1}, min, max);
+	CHECK(min == 1);
+	CHECK(max == 1);
+}
+