diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 442a728..c58c1ae 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -31,13 +31,13 @@ jobs:
         uses: ./
         with:
           source-dir: test
-          build-dir: test/build
+          build-dir: output
 
       - name: Run the build result
-        run: test/build/hello_world
+        run: output/hello_world
 
       - name: Check if the default build directory does not exist
-        run: test ! -d build
+        run: test ! -d build && test ! -d test/build
 
   additional-flags-usage:
     runs-on: ${{ matrix.compiler == 'msvc' && 'windows' || 'ubuntu' }}-latest
@@ -59,8 +59,8 @@ jobs:
 
       - name: Run the build results
         run: |
-          ${{ matrix.compiler == 'msvc' && 'build\Debug\test_c.exe' || 'build/test_c' }}
-          ${{ matrix.compiler == 'msvc' && 'build\Debug\test_cpp.exe' || 'build/test_cpp' }}
+          ${{ matrix.compiler == 'msvc' && 'test\build\Debug\test_c.exe' || 'test/build/test_c' }}
+          ${{ matrix.compiler == 'msvc' && 'test\build\Debug\test_cpp.exe' || 'test/build/test_cpp' }}
 
   specified-compiler-usage:
     runs-on: ${{ matrix.os }}-latest
@@ -82,7 +82,7 @@ jobs:
           args: -D CHECK_USING_CLANG=ON
 
       - name: Run the build results
-        run: build/test_c && build/test_cpp
+        run: test/build/test_c && test/build/test_cpp
 
   specified-generator-usage:
     runs-on: ${{ matrix.os }}-latest
@@ -100,4 +100,4 @@ jobs:
           generator: Ninja
 
       - name: Run the build result
-        run: build/hello_world
+        run: test/build/hello_world
diff --git a/action.yml b/action.yml
index af61157..1461fcd 100644
--- a/action.yml
+++ b/action.yml
@@ -8,11 +8,9 @@ inputs:
   source-dir:
     description: Source directory of the CMake project
     required: false
-    default: .
   build-dir:
     description: Build directory of the CMake project
     required: false
-    default: build
   targets:
     description: List of build targets
     required: false
@@ -41,8 +39,18 @@ runs:
       id: process_inputs
       shell: bash
       run: |
-        ARGS="'${{ inputs.source-dir }}' -B '${{ inputs.build-dir }}'"
-        BUILD_ARGS="--build '${{ inputs.build-dir }}'"
+        SOURCE_DIR="."
+        if [ -n '${{ inputs.source-dir }}' ]; then
+          SOURCE_DIR="${{ inputs.source-dir }}"
+        fi
+        BUILD_DIR="build"
+        if [ -n '${{ inputs.build-dir }}' ]; then
+          BUILD_DIR="${{ inputs.build-dir }}"
+        elif [ -n "${{ inputs.source-dir }}" ]; then
+          BUILD_DIR="${{ inputs.source-dir }}/build"
+        fi
+        ARGS="'$SOURCE_DIR' -B '$BUILD_DIR'"
+        BUILD_ARGS="--build '$BUILD_DIR'"
         if [ -n '${{ inputs.targets }}' ]; then
           BUILD_ARGS="$BUILD_ARGS --target ${{ inputs.targets }}"
         fi