diff --git a/test/.gitignore b/test/.gitignore
new file mode 100644
index 0000000..7de0b67
--- /dev/null
+++ b/test/.gitignore
@@ -0,0 +1 @@
+*.output
diff --git a/test/Makefile b/test/Makefile
new file mode 100644
index 0000000..e85c565
--- /dev/null
+++ b/test/Makefile
@@ -0,0 +1,29 @@
+CC = cc
+AR = ar
+RM = rm -f
+
+.c.o:
+	$(CC) -c -o $@ $< -I..
+
+all:	test
+
+test:	exec_test1
+
+exec_test1:	test1
+	@echo "Test1..."
+	@./test1 | tee test1.output 2>&1
+	@if diff -u test1.expected test1.output; then \
+		echo "Test1: passed."; \
+	else \
+		echo "Test1: failed."; \
+	fi
+
+test1.o:	test1.c ../longnumber.h
+
+test1:	test1.o ../liblongnumber.a
+	$(CC) -o test1 test1.o -llongnumber -L..
+
+clean::
+	$(RM) test1
+	$(RM) test1.o
+	$(RM) test1.output
diff --git a/test/test1.c b/test/test1.c
new file mode 100644
index 0000000..ce8c03e
--- /dev/null
+++ b/test/test1.c
@@ -0,0 +1,78 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "longnumber.h"
+
+void test_ln_create01(void)
+{
+    LongNumber *a;
+    a = ln_create(10, 0, 0);
+    ln_print(a, 10+1, "c01");
+    ln_free(a);
+}
+
+void test_ln_create02(void)
+{
+    LongNumber *a;
+    a = ln_create(10, 1, 3);
+    ln_print(a, 10+1, "c02");
+    ln_free(a);
+}
+
+void test_ln_create03(void)
+{
+    LongNumber *a;
+    a = ln_create(10, 2, 3);
+    ln_print(a, 10+1, "c03");
+    ln_free(a);
+}
+
+void test_ln_add01(void)
+{
+    LongNumber *a, *b;
+    a = ln_create(10, 0, 0);
+    b = ln_create(10, 0, 0);
+    ln_add(b, b, a, 10);
+    ln_print(b, 10+1, "a01");
+    ln_free(a);
+    ln_free(b);
+}
+
+void test_ln_add02(void)
+{
+    LongNumber *a, *b;
+    a = ln_create(10, 1, 3);
+    b = ln_create(10, 2, 3);
+    ln_add(b, b, a, 10);
+    ln_print(b, 10+1, "a02");
+    ln_free(a);
+    ln_free(b);
+}
+
+void test_ln_add03(void)
+{
+    LongNumber *a, *b;
+    a = ln_create(10, 2, 3);
+    b = ln_create(10, 2, 3);
+    ln_add(b, b, a, 10);
+    ln_print(b, 10+1, "a03");
+    ln_free(a);
+    ln_free(b);
+}
+
+int main(void)
+{
+    unsetenv("COLUMNS");
+
+    ln_init(4);
+    test_ln_create01();
+    test_ln_create02();
+    test_ln_create03();
+    test_ln_add01();
+    test_ln_add02();
+    test_ln_add03();
+
+    ln_init(1);
+    test_ln_create01();
+
+    return 0;
+}
diff --git a/test/test1.expected b/test/test1.expected
new file mode 100644
index 0000000..6e59098
--- /dev/null
+++ b/test/test1.expected
@@ -0,0 +1,13 @@
+c01   0.0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 (   1-  40)
+        0000 (  41-  44)
+c02   0.3333 3333 3333 3333 3333 3333 3333 3333 3333 3333 (   1-  40)
+        3333 (  41-  44)
+c03   0.6666 6666 6666 6666 6666 6666 6666 6666 6666 6666 (   1-  40)
+        6666 (  41-  44)
+a01   0.0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 (   1-  40)
+        0000 (  41-  44)
+a02   0.9999 9999 9999 9999 9999 9999 9999 9999 9999 9999 (   1-  40)
+        9999 (  41-  44)
+a03   1.3333 3333 3333 3333 3333 3333 3333 3333 3333 3333 (   1-  40)
+        3332 (  41-  44)
+c01   0.0 0 0 0 0 0 0 0 0 0 0 (   1-  11)