In Java, interpret nested do/while and while statements formatted on separate lines. What is printed? public class Test { public static void main(String[] args) { int I = 1; do while (I < 1) System.out.print("I is " + I); while (I > 1); } }
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AI is 1
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BI is 1 I is 1
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CNo output is produced.
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DCompilation error
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EI is 0
Answer
Correct Answer: No output is produced.
Explanation
Introduction / Context:This classic formatting puzzle tests how Java parses a do-while statement whose body is itself a while statement. The key is understanding statement boundaries and which loop actually executes.
Given Data / Assumptions:
Iis initialized to 1.- The
dostatement's body is a singlewhilestatement:while (I < 1) System.out.print(...); - After that body completes, the trailing
while (I > 1);is the terminator of thedoloop.
Concept / Approach:Evaluate the inner while (I < 1) first: since I == 1, it executes zero times and prints nothing. Then the outer do-while checks its condition (I > 1), which is false, so the entire construct ends with no output.
Step-by-Step Solution:Inner while condition: I < 1 ⇒ false at entry ⇒ body never runs.The do executes its single statement (the inner while) exactly once (doing nothing).Outer terminating condition: I > 1 ⇒ false; loop finishes.No print statements were executed ⇒ no output.
Verification / Alternative check:Change I to 0 and you will see "I is 0" printed repeatedly until the outer condition stops it (it still won’t in this exact shape without changing I).
Why Other Options Are Wrong:They assume the print executes at least once or a compilation problem; the code is valid and the inner condition is false.
Common Pitfalls:Misreading line breaks as scoping braces; Java does not add implicit blocks based on newlines or indentation.
Final Answer:No output is produced.