diff --git a/src/fs_reader.cpp b/src/fs_reader.cpp
index 6bf40cc..8e12456 100644
--- a/src/fs_reader.cpp
+++ b/src/fs_reader.cpp
@@ -1,4 +1,7 @@
+#include <exception>
 #include <iostream>
+#include <stdexcept>
+#include <system_error>
 #include <vector>
 #include <filesystem>
 #include <queue>
@@ -6,18 +9,18 @@
 namespace fs = std::filesystem;
 using std::vector, std::queue;
 
-int validate(const fs::path path) {
+bool valid(const fs::path path) {
     if(!fs::exists(path))
-        return 1;
+        return false;
 
-    if (false)
-        return 1;
+    if (!fs::is_directory(path))
+        return false;
 
-    return 0;
+    return true;
 }
 
 vector<fs::path> find_all_files(const fs::path path) {
-    if (validate(path) == 1)
+    if (valid(path))
         return vector<fs::path>(0);
 
     vector<fs::path> files;
@@ -25,11 +28,16 @@ vector<fs::path> find_all_files(const fs::path path) {
     folders_to_traverse.push(path);
 
     while (!folders_to_traverse.empty()) {
-        for (const fs::directory_entry &entry : fs::directory_iterator(folders_to_traverse.front()))
-            if (!entry.is_directory())
-                files.emplace_back(entry);
-            else
-                folders_to_traverse.push(entry);
+        try {
+            for (const fs::directory_entry &entry : fs::directory_iterator(folders_to_traverse.front())) {
+                if (!entry.is_directory())
+                    files.emplace_back(entry);
+                else
+                    folders_to_traverse.push(entry);
+            }
+        } catch (std::exception &system_error) {
+            system_error.what();
+        }
 
         folders_to_traverse.pop();
     }
@@ -39,7 +47,7 @@ vector<fs::path> find_all_files(const fs::path path) {
 }
 
 vector<fs::path> find_all_folders(const fs::path path) {
-    if (validate(path) == 1)
+    if (valid(path))
         return vector<fs::path>(0);
 
     vector<fs::path> folders;
@@ -61,7 +69,7 @@ vector<fs::path> find_all_folders(const fs::path path) {
 }
 
 vector<fs::path> find_all_files_and_folders(const fs::path path) {
-    if (validate(path) == 1)
+    if (valid(path))
         return vector<fs::path>(0);
 
     vector<fs::path> files_and_folders;
diff --git a/src/fs_reader.hpp b/src/fs_reader.hpp
index 446c70f..dd55b65 100644
--- a/src/fs_reader.hpp
+++ b/src/fs_reader.hpp
@@ -3,4 +3,5 @@
 
 std::vector<std::filesystem::path> find_all_files(const std::filesystem::path path);
 std::vector<std::filesystem::path> find_all_folders(const std::filesystem::path path);
-std::vector<std::filesystem::path> find_all_files_and_folders(const std::filesystem::path path);
\ No newline at end of file
+std::vector<std::filesystem::path> find_all_files_and_folders(const std::filesystem::path path);
+bool valid(std::filesystem::path path);
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 63ed357..0a92b68 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2,9 +2,22 @@
 #include <vector>
 #include <filesystem>
 #include "fs_reader.hpp"
+#include "openssl/md5.h"
 namespace fs = std::filesystem;
 using std::cout, std::vector;
 
+void checksum_md5(const fs::path path) {
+    unsigned char digest[16];
+    MD5_CTX ctx;
+    MD5_Init(&ctx);
+    MD5_Update(&ctx, reinterpret_cast<unsigned char*>(const_cast<char*>(path.c_str())), path.string().size());
+    MD5_Final(digest, &ctx);
+
+    for (int i = 0; i < 16; i++)
+        printf("%02x", digest[i]);
+    putchar ('\n');
+}
+
 int main(int argc, char *argv[]) {
     if (argc == 1) {
         cout << "chksum: No path specified\n";
@@ -14,14 +27,17 @@ int main(int argc, char *argv[]) {
         cout << "chksum: Too many arguments\n";
         return 1;
     }
-    if (!fs::exists(argv[1])) {
+    if (!valid(argv[1])) {
         cout << "chksum: Not a valid path\n";
         return 1;
     }
 
-    vector<fs::path> files_and_folders = find_all_files(argv[1]);
+    checksum_md5("hello world");
+    return 0;
 
-    for (const fs::path &path : files_and_folders)
+    vector<fs::path> files = find_all_files(argv[1]);
+
+    for (const fs::path &path : files)
         cout << path << "\n";
 
     return 0;