diff --git a/unittest.cpp b/unittest.cpp
new file mode 100644
index 0000000..37074ec
--- /dev/null
+++ b/unittest.cpp
@@ -0,0 +1,55 @@
+#define DOCTEST_CONFIG_NO_MULTITHREADING
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "doctest.h"
+#include "histogram_internal.h"
+
+TEST_CASE("distinct positive numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({1, 2}, min, max);
+    CHECK(min == 1);
+    CHECK(max == 2);
+}
+TEST_CASE("distinct negative numbers"){
+    double min = 0;
+    double max = 0;
+    find_minmax({-1, -2}, min, max);
+    CHECK(min == -2);
+    CHECK(max == -1);
+}
+TEST_CASE("vector of the same elements"){
+    double min = 0;
+    double max = 0;
+    find_minmax({3,3,3}, min, max);
+    CHECK(min == 3);
+    CHECK(max == 3);
+}
+TEST_CASE("vector of one elements"){
+    double min = 0;
+    double max = 0;
+    find_minmax({3}, min, max);
+    CHECK(min == max);
+}
+TEST_CASE("mixed positive and negative numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({-1, 2, 0, -3, 5}, min, max);
+    CHECK(min == -3);
+    CHECK(max == 5);
+}
+
+TEST_CASE("vector with all negative numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({-5, -10, -2}, min, max);
+    CHECK(min == -10);
+    CHECK(max == -2);
+}
+
+TEST_CASE("vector with zero") {
+    double min = 0;
+    double max = 0;
+    find_minmax({0, -1, 1}, min, max);
+    CHECK(min == -1);
+    CHECK(max == 1);
+}
diff --git a/unittest.depend b/unittest.depend
new file mode 100644
index 0000000..4bddb1d
--- /dev/null
+++ b/unittest.depend
@@ -0,0 +1,8 @@
+# depslib dependency file v1.0
+1746270053 source:c:\users\professional\desktop\cs-lab34\lab1\histogram.cpp
+	"histogram.h"
+
+1746269334 c:\users\professional\desktop\cs-lab34\lab1\histogram.h
+	<vector>
+	<iostream>
+