Add comments

text-file-database.py

@@ -1,5 +1,7 @@
+# math used for rounding down
 import math
 
+# add new user's info to end of file
 def insert(lines):
     print("ID:", math.floor(len(lines)/3))
     lines.append(input("Name: ") + " \n")
@@ -7,6 +9,7 @@ def insert(lines):
     lines.append(input("School year: ") + " \n")
     return lines
 
+# remove user's info from file, by user ID
 def delete(lines):
     id = input("ID: ")
     for i in range(math.floor(len(lines)/3)):
@@ -16,6 +19,7 @@ def delete(lines):
             lines.pop(i*3)
     return lines
 
+# print a user's info from file, by user ID
 def select(lines):
     id = input("ID: ")
     for i in range(math.floor(len(lines)/3)):
@@ -24,6 +28,7 @@ def select(lines):
         else:
             print("ID not found")
 
+# replace a user's info in file, by user ID
 def replace(lines):
     id = input("ID: ")
     for i in range(math.floor(len(lines)/3)):
@@ -41,27 +46,40 @@ def replace(lines):
             lines.pop(i*3)
     return lines
 
+# attempt to open file
 try:
     file = open("data.txt","r+")
+# if file doesn't exist, create it
 except:
     file = open("data.txt","w+")
+# read the lines from the file
 lines = file.readlines()
+# run until user chooses to exit
 while True:
+    # print each user's info, one user per line
     for i in range(math.floor(len(lines)/3)):
+        # only print the content if the file isn't empty
         if len(lines) > 2:
             print("\n" + str(i) + " - name:", lines[i*3].strip(" \n") + ", age:", lines[i*3+1].strip(" \n") + ", school year:", lines[i*3+2].strip(" \n") + "\n")
+    # ask the user which function they want to perform
     function = input("Function (insert, i; delete, d; select, s; replace, r; exit, e): ")
+    # add user to file
     if function.strip(" ") == "i":
         lines = insert(lines)
         file.writelines(lines)
+    # remove user from file
     elif function.strip(" ") == "d":
         lines = delete(lines)
         file.writelines(lines)
+    # print user's info from file
     elif function.strip(" ") == "s":
         select(lines)
+    # replace user's info in file
     elif function.strip(" ") == "r":
         lines = replace(lines)
         file.writelines(lines)
+    # exit the program by breaking the loop
     elif function.strip(" ") == "e":
         break
+# close the file
 file.close()