Question

question 3

what is the output of the following code ?

java
public class loop
{
public static void main (string args) throws ioexception
{
int i = 1;
while( i <= 5 )
{
int a = 0, j = 1;
while( j <= 1 )
{
a += j;
j++;
}
system.out.print(j + \ \);
i++;
}
}
}

a)
1 1 1 1 1

b)
1 2 3 4 5

c)
5 4 3 2 1

d)
2 2 2 2 2

Explanation:

🆕 New Concept Discovered: Nested Loop Execution
Tracing variables step-by-step through inner and outer loops.

Step 1: Analyze the outer loop structure

The outer loop is controlled by the variable i, which starts at 1. The loop continues as long as i <= 5.
Inside this loop, several actions happen sequentially:

1. Local variables a and j are re-initialized: int a = 0, j = 1;.
2. An inner while loop runs.
3. The value of j is printed followed by a space: System.out.print(j + " ");.
4. i is incremented: i++;.

Step 2: Trace the inner loop execution

Let's look at what happens to j inside the inner loop during any single iteration of the outer loop:

• Before the inner loop starts, j is initialized to 1.
• The inner loop condition is while (j <= 1).
• Since j is 1, the condition 1 <= 1 is true, so the loop body executes:
• a += j; (adds 1 to a)
• j++; (increments j to 2)
• The condition is checked again: while (j <= 1). Since j is now 2, the condition 2 <= 1 is false, and the inner loop terminates.

At this point, the value of j is 2.

Step 3: Trace the print statement and outer loop iterations

After the inner loop terminates, the program executes:

System.out.print(j + " ");

Since j is 2, this prints 2 .

Then, i is incremented (i++), and the outer loop moves to the next iteration.

Because a and j are declared and re-initialized to 0 and 1 respectively at the start of every outer loop iteration, this exact process repeats for every value of i from 1 to 5:

• Iteration 1 (i = 1): Inner loop runs, j becomes 2, prints 2 .
• Iteration 2 (i = 2): Inner loop runs, j becomes 2, prints 2 .
• Iteration 3 (i = 3): Inner loop runs, j becomes 2, prints 2 .
• Iteration 4 (i = 4): Inner loop runs, j becomes 2, prints 2 .
• Iteration 5 (i = 5): Inner loop runs, j becomes 2, prints 2 .

After i becomes 6, the outer loop condition i <= 5 becomes false, and the program terminates. The total printed output is 2 2 2 2 2 .

Answer:

d (which corresponds to 22222)