diff --git a/.gitignore b/.gitignore
index 07ed706..73a7ce5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,5 @@
-build/*
\ No newline at end of file
+build/*
+CMakeFiles
+CMakeCache.txt
+cmake_install.cmake
+Makefile
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9934fa7..2e3d5f0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,8 +2,8 @@ cmake_minimum_required(VERSION 3.6)
 
 set(PROJECT_N hello)
 
-SET(CMAKE_C_COMPILER /home/user/Android/Sdk/ndk/21.0.6113669/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android22-clang)
-SET(CMAKE_CXX_COMPILER /home/user/Android/Sdk/ndk/21.0.6113669/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android22-clang++)
+SET(CMAKE_C_COMPILER $ENV{NDK}/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android22-clang)
+SET(CMAKE_CXX_COMPILER $ENV{NDK}/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android22-clang++)
 
 project(${PROJECT_N} VERSION 1.0)
 
diff --git a/ReadMe.md b/ReadMe.md
new file mode 100644
index 0000000..e128ff9
--- /dev/null
+++ b/ReadMe.md
@@ -0,0 +1 @@
+编译时修改build.sh中的ndk路径
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..9404faf
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,3 @@
+export NDK=/home/user/Android/Sdk/ndk/21.0.6113669/
+cmake CMakeLists.txt
+make