Add support for multiple files in cat command

Author: zohrehKazemianpour

implement-shell-tools/cat/cat.py

@@ -9,41 +9,42 @@
 
 parser.add_argument("-n", "--number", action="store_true", help="Number all output lines")
 parser.add_argument("-b", "--number-nonblank", action="store_true", help="Number non-empty lines only")
-parser.add_argument("path", help="File to read")
+parser.add_argument("paths", nargs='+', help="Files to read")
 
 args = parser.parse_args()
 
-# Read the file 
-with open(args.path, "r") as f: 
-    content = f.read()
-                
+line_number = 0  # Shared counter across all files
 
-# Check if numbering is needed
-if args.number:
-    lines = content.split("\n")
-    numbered_lines = []
+# Process each file
+for path in args.paths:  # LEVEL 1: for loop starts
+    with open(path, "r") as f:  # LEVEL 2: inside for loop
+        content = f.read()  # LEVEL 3: inside with block
 
-    for index, line in enumerate(lines):
-        line_number = index + 1
-        numbered_line = f"{line_number:6}\t{line}"  # Format with tab like real cat
-        numbered_lines.append(numbered_line)
-    
-    print("\n".join(numbered_lines))
-
-elif args.number_nonblank:
-    lines = content.split("\n")
-    numbered_lines = []
-    line_number = 0
-    
-    for line in lines:
-        if line.strip() == "":  # Empty line
-            numbered_lines.append(line)  # Don't number it
-        else:  # Non-empty line
-            line_number = line_number + 1
+    # Check if numbering is needed
+    if args.number:  # LEVEL 2: inside for loop
+        lines = content.split("\n")  # LEVEL 3: inside if
+        numbered_lines = []
+        
+        for index, line in enumerate(lines):  # LEVEL 3: inside if
+            line_number = line_number + 1  # LEVEL 4: inside inner for
             numbered_line = f"{line_number:6}\t{line}"
             numbered_lines.append(numbered_line)
+        
+        print("\n".join(numbered_lines))  # LEVEL 3: inside if
 
-    print("\n".join(numbered_lines))    
+    elif args.number_nonblank:  # LEVEL 2: inside for loop
+        lines = content.split("\n")  # LEVEL 3: inside elif
+        numbered_lines = []
+        
+        for line in lines:  # LEVEL 3: inside elif
+            if line.strip() == "":  # LEVEL 4: inside inner for
+                numbered_lines.append(line)
+            else:
+                line_number = line_number + 1
+                numbered_line = f"{line_number:6}\t{line}"
+                numbered_lines.append(numbered_line)
+        
+        print("\n".join(numbered_lines))
 
-else:
-    print(content)
+    else:  # LEVEL 2: inside for loop
+        print(content)  # LEVEL 3: inside else