Question

Which of the following loops will print out the numbers 3, 5, 7, 9, 11?

I.
int i=1;
while(i<10)
{
i=i+2;
System.out.println(i);
}

II.
int i=3;
while(i<=11)
{
System.out.println(i);
i=i+2;
}

III.
for(int i=4;i<=12;i=i+2)
{
System.out.println(i-1);
}

Answer 1

The loop that will print out the numbers 3, 5, 7, 9, 11 is Loop II.

Explanation:

Loop II initializes the variable 'i' to 3 and runs a 'while' loop until 'i' is less than or equal to 11. Inside the loop, it first prints the value of 'i' and then increments 'i' by 2. This sequence effectively prints the odd numbers from 3 to 11 inclusive, meeting the criteria of printing 3, 5, 7, 9, 11.

In Loop I, the 'while' loop initializes 'i' to 1 and increments 'i' by 2 in each iteration before printing 'i'. However, it starts printing from 3 and continues up to 9, excluding 11.

Loop III uses a 'for' loop with 'i' initialized to 4 and increments 'i' by 2 in each iteration. However, before printing 'i', it subtracts 1, resulting in the loop printing even numbers starting from 3 and going up to 11.

The crucial distinction lies in the sequence and initialization of the loop variables. Loop II specifically begins with 3 and proceeds with increments by 2, printing the odd numbers within the specified range, making it the correct loop that produces the sequence 3, 5, 7, 9, 11.