diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..aa6070c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+KoreanNumbers
+src/*.o
+
+compile_commands.commands.json
+compile_commands.json
+.clangd/
diff --git a/Makefile b/Makefile
index 621d2a2..977a5d0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-COMMON_CXXFLAGS = -Wall -Wextra -Wpedantic
+COMMON_CXXFLAGS = -Wall -Wextra -Wpedantic -std=c++20
 ifdef DEBUG
 	CXXFLAGS = -O0 -g ${COMMON_CXXFLAGS}
 else
diff --git a/src/main.cpp b/src/main.cpp
index 11b7fad..b92104e 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,3 +1,53 @@
+#include <cstdio>
+#include <cstring>
+#include <cstdlib>
+#include <random>
+#include <chrono>
+#include <memory>
+#include <string>
+#include <iostream>
+
+const wchar_t* won = L"원";
+const wchar_t* ship = L"십";
+const wchar_t* bec = L"백";
+const wchar_t* chun = L"천";
+const wchar_t* man = L"만";
+const wchar_t* uc = L"억";
+
+void help() {
+    puts("Usage:");
+    puts("  --max <integer> - set maximum value for generated value (default 999,999,999,999)");
+}
+
+std::wstring value_to_korean(unsigned long long value) {
+    return L"UNIMPLEMENTED";
+}
+
 int main(int argc, char **argv) {
+    unsigned long long max = 999999999999;
+
+    --argc; ++argv;
+    while(argc > 0) {
+        if(std::strcmp(argv[0], "--max") == 0 && argc > 1) {
+            --argc; ++argv;
+            max = std::strtoull(argv[0], nullptr, 0);
+        }
+        --argc; ++argv;
+    }
+
+    printf("Maximum value is set to %llu\n", max);
+
+    unsigned long long value;
+    {
+        std::default_random_engine r_eng(std::chrono::steady_clock::now().time_since_epoch().count());
+        std::uniform_int_distribution<unsigned long long> r_dist(0, max);
+        value = r_dist(r_eng);
+    }
+
+    printf("\nGot value \"%llu\", hit enter to continue...", value);
+    std::cin.get();
+
+    std::wcout << "Result: " << value_to_korean(value) << std::endl;
+
     return 0;
 }