Difficulty: Medium
Correct Answer: 51
Explanation:
Introduction / Context:
This problem focuses on Java control flow: short-circuit logic, default initialization of static booleans, and especially the effect of a stray semicolon after an if (a “dangling semicolon”).
Given Data / Assumptions:
b
is a static boolean with default value false
.hand = 42
.if (hand > 50)
on Line 9.
Concept / Approach:
Evaluate conditions stepwise. if (hand < 50 && !b)
is true, so hand++
executes. The second if has a semicolon as its statement, so the subsequent else if
pairs with that if but the then-part is a no-op. The else-if block can still run depending on the condition outcome.
Step-by-Step Solution:
Initially: hand = 42
, b = false
. Check hand < 50 && !b
→ 42 < 50
and !false
→ true → hand++
→ hand = 43
. Next: if (hand > 50);
→ condition is false but the statement is the semicolon (does nothing). The else if (hand > 40)
now evaluates: 43 > 40
→ true → execute block. Block does hand += 7
→ 50, then hand++
→ 51. Prints 51.
Verification / Alternative check:
Remove the semicolon on Line 9; then the else-if would be associated normally, producing a different flow depending on the updated value of hand
.
Why Other Options Are Wrong:
41 or 42 ignore the first increment; 50 ignores the second increment; 49 cannot occur under the shown path.
Common Pitfalls:
Not noticing the stray semicolon; misunderstanding how else
binds to the nearest unmatched if
; ignoring default values of static primitives.
Final Answer:
51
Discussion & Comments