diff --git a/PointCloudRegistration/main.cpp b/PointCloudRegistration/main.cpp
index d7ba933..1cf8adc 100644
--- a/PointCloudRegistration/main.cpp
+++ b/PointCloudRegistration/main.cpp
@@ -39,6 +39,15 @@ const double SAC_MAX_CORRESPONDENCE_DIST = 1000; // 2000
 const double SAC_MIN_CORRESPONDENCE_DIST = 3;
 
 int main(int argc, char *argv[]){
+	string filename1, filename2;
+	if (argc == 3){
+		filename1 = argv[1];
+		filename2 = argv[2];
+	} else{
+		filename1 = "pcd/a3.pcd";
+		filename2 = "pcd/a4.pcd";
+	}
+
 	time_t starttime = time(NULL);
 	cout << "Loading clouds...\n";
 	cout.flush();
@@ -47,8 +56,8 @@ int main(int argc, char *argv[]){
 	pcl::PointCloud<pcl::PointXYZ>::Ptr cloud1(new pcl::PointCloud<pcl::PointXYZ>);
 	pcl::PointCloud<pcl::PointXYZ>::Ptr cloud2(new pcl::PointCloud<pcl::PointXYZ>);
 	
-	pcl::io::loadPCDFile("pcd/a3.pcd", *cloud1);
-	pcl::io::loadPCDFile("pcd/a4.pcd", *cloud2);
+	pcl::io::loadPCDFile(filename1, *cloud1);
+	pcl::io::loadPCDFile(filename2, *cloud2);
 
 	// downsample the clouds
 	pcl::PointCloud<pcl::PointXYZ>::Ptr cloud1ds(new pcl::PointCloud<pcl::PointXYZ>);
diff --git a/Readme.md b/Readme.md
index 9e2a574..0d6b07c 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,4 +1,11 @@
 SCA-IA
 ===
-SCA-IA point cloud registration
-Developed By VS2013update5 and PCL(Point Cloud Library)
\ No newline at end of file
+SCA-IA point cloud registration and ICP to solve RT matrix
+Developed By VS2013update5 and PCL(Point Cloud Library)
+
+use program in cmd:
+
+```
+PointCloudRegistration.exe source.pcd target.pcd
+```
+