OCR J277 - String Methods Revision

1 [3 Marks]

ASC('A')=65. ASC('a')=97.
Calculate:

CHR(ASC('A') + 3)
ASC('c') - ASC('a')
CHR(50) (Note: '0' is 48)

✅ Mark Scheme

D (68)
2 (99 - 97)
'2' (Character 2, not integer 2)

Score:

2 [2 Marks]

01 command = input("Enter command: ") 02 if command == "START": 03 print("Game Starting...") 04 else: 05 print("Unknown command")

(a) Why does "Start" fail?
(b) Rewrite IF statement to accept any case (using upper/lower).

✅ Mark Scheme

(a) Case-sensitive comparison. "Start" != "START".

(b) if command.upper() == "START":

Score:

3 [4 Marks]

text = "ROBOT" newText = "" count = 0 WHILE count < 3 letter = text.substring(count, 1) newText = newText + letter + "-" count = count + 1 ENDWHILE print(newText)

Trace output.

Trace Table:

count	letter	newText	Output

✅ Mark Scheme

Output: R-O-B-

(Loops 0, 1, 2. Extracts R, O, B. Appends hyphen each time).

Score:

4 [6 Marks]

Write a function getInitials(name) that returns uppercase initials.
e.g. "alan turing" -> "AT".

✅ Mark Scheme

function getInitials(name)
  first = name.substring(0, 1)
  spacePos = name.index(" ")
  second = name.substring(spacePos + 1, 1)
  combined = first + second
  return combined.upper()
endfunction

Score:

5 [2 Marks]

name = "ben" name.upper() print(name)

Output is "ben". Why? Fix logic.

✅ Mark Scheme

Reason: String methods return a new string, they don't change the original.

Fix: name = name.upper()

Score:

6 [3 Marks]

surname = input("Enter surname: ") part1 = surname.........................(3) # Get first 3 letters part2 = surname......................... # Get the number of characters username = part1 + .....................(part2) # Join them (requires casting) print(username)

Fill blanks (First 3 letters + Length).

✅ Mark Scheme

1. left (or substring)
2. length
3. str (Must cast int length to string)

Score:

7 [3 Marks]

module = "Computer Science"
Output of:

module.substring(0, 4)
module.right(3)
module.length

✅ Mark Scheme

Comp
nce
16

Score:

8 [4 Marks]

Write a WHILE loop that asks for password until length >= 8.

✅ Mark Scheme

pw = input("Password: ")
while len(pw) < 8:
    print("Too short")
    pw = input("Password: ")

Score:

9 [3 Marks]

word1 = "Apple", word2 = "Zebra"
True or False:

word1.length == 5
word1 < word2
word1.substring(0, 1) == "a"

✅ Mark Scheme

True
True (Apple < Zebra alphabetically)
False ("A" != "a")

Score:

Topic 2.2.6: String Manipulation