Consider the given code snippet : int j = 10; do {
MessageBox.Show(j); j-= 1; } while (j =0); Which is the correct way to rewrite the above code?

Question

Consider the given code snippet : int j = 10; do {
MessageBox.Show(j); j-= 1; } while (j >=0); Which is the correct way to rewrite the above code?

BlackTom AI · Accepted Answer

Examining the transformation from a do-while loop to an equivalent loop construct requires matching both behavior and control flow.
Option 1: int j; for (j = 10; j >= 0; j--) MessageBox.Show(j);
This option uses a for-loop that initializes j (without explicitly declaring it in the same statement as others), checks the condition j >= 0, and decrements j each iteration. It will execute for j = 10 down to j = 0 inclusive, which matches the original do-while behavior where j starts at 10 and decreases after each display as long as the condition j >= 0 holds. The loop body corresponds directly to MessageBox.Show(j);, making this a valid rewrite.
Option 2: int j = 10; do while ( j >= 0){ MessageBox.Show(j); j-= 1;}
This option attempts a do-while structure but places the condition after the block in the form "do while (...) { ... }". The correct C# syntax for a do-while has the condition after the closing brace as "do { ... } while (condition);". The provided form is invalid syntax in C#, so this is not a correct rewrite.
Option 3: int j = 10; while (j > 0){ MessageBox.Show(j); j -= 1; }
This option uses a while-loop with the condition j > 0. The original loop continues while j >= 0, i.e., it also runs when j equals 0. By stopping at j > 0, this version omits the final iteration where j equals 0, changing the observable behavior and thus is not a faithful rewrite.
Option 4: int j = 10; do{ MessageBox.Show(j);} until (j >=0);
This option employs a do block, which is fine to mimic the do-while structure, but it uses an "until" keyword and a condition (j >= 0) in that form. In C#, there is no "until" keyword for loops; the equivalent syntax uses "while (condition)". The presence of "until" makes this invalid C# syntax and not a proper rewrite.
In summary, the key aspects are preserving the exact number of iterations and the condition that governs continuation. Only Option 1 preserves the behavior (including the iteration when j reaches 0) and uses a valid loop construct with correct initialization, condition, and update semantics. The other options either introduce syntax errors, alter the loop’s termination condition, or rely on an unsupported construct, which breaks equivalence with the original snippet.

Consider the given code snippet : int j = 10; do { MessageBox.Show(j); j-= 1; } while (j >=0); Which is the correct way to rewrite the above code?单项选择题

类似问题

Match each loop definition with how many iterations it’ll run for. 1: for k=1:2:10 2: for k=[3,7,10] 3: while 4<pi 4: for k=linspace(1,10,10)

Which of the following pseudocode statements represents a repetition statement?

Which of the following is a drawback of while loops?

For loops are more adaptable than while loops.

A(n) _____ specifically executes some block of code repeatedly as long as a given condition is true.

A(n) _____ allows programmers to repeat a block of statements in their program without having to retype any of the actual code or explicitly define and call a method.

Analyze the code snippet below and identify the output produced on the Listbox lstOutput. int i, j=0; for (i = 20; i >= 10; i-=2) { j = 2; while (i % j == 2) { j++; } lstOutput.Items.Add (i.ToString() + " " + j.ToString()); }

Analyze the code snippet below and identify the output produced on the Listbox lstOutput. int i, j=0; for (i = 20; i >= 10; i-=2) { j = 2; while (i % j == 2) { j++; } lstOutput.Items.Add (i.ToString() + " " + j.ToString()); }

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单