diff --git a/main.c b/main.c
new file mode 100644
--- /dev/null
+++ b/main.c
@@ -0,0 +1,23 @@
+#include <stdio.h>
+
+int func(int num);
+void print_int(int num);
+
+int main() {
+	int i;
+
+	for (i = 0; i < 10; i++) {
+		print_int(func(i));
+	}
+
+	return 0;
+}
+
+int func(int num) {
+	return num * num;
+}
+
+void print_int(int num) {
+	printf("%d", num);
+}
+
