Continue statement with levels in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to skip the current iteration in the inner loop.

PHP

<?php
for ($i = 1; $i <= 3; $i++) {
    for ($j = 1; $j <= 3; $j++) {
        if ($j == 2) {
            [1];
        }
        echo "$i,$j\n";
    }
}
?>

Drag options to blanks, or click blank then click option'

Areturn

Bbreak

Cexit

Dcontinue

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'break' instead of 'continue' which exits the loop instead of skipping iteration.

The continue statement skips the current iteration of the loop it is in. Here, it skips when $j == 2 in the inner loop.

2fill in blank

medium

Complete the code to skip the current iteration of the outer loop using continue with level.

PHP

<?php
for ($i = 1; $i <= 3; $i++) {
    for ($j = 1; $j <= 3; $j++) {
        if ($j == 2) {
            [1] 2;
        }
        echo "$i,$j\n";
    }
}
?>

Drag options to blanks, or click blank then click option'

Areturn

Bbreak

Ccontinue

Dexit

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'break 2;' which exits the outer loop instead of continuing it.

The continue 2; statement skips the current iteration of the outer loop (two levels up).

3fill in blank

hard

Fix the error in the continue statement to skip the outer loop iteration.

PHP

<?php
for ($x = 1; $x <= 3; $x++) {
    for ($y = 1; $y <= 3; $y++) {
        if ($y == 3) {
            [1] 2;
        }
        echo "$x,$y\n";
    }
}
?>

Drag options to blanks, or click blank then click option'

Acontinue

Bcontinue;

Ccontinue 3

Dcontinue 1

Attempts:

3 left

💡 Hint

Common Mistakes

Including the semicolon inside the blank causing syntax error.

Using wrong level number.

The correct syntax is continue 2; without a semicolon inside the blank. The blank replaces only the keyword and level number together, so the blank must be 'continue'. The number 2 is already in the code after the blank.

4fill in blank

hard

Fill both blanks to skip the current iteration of the inner loop and continue the outer loop.

PHP

<?php
for ($a = 1; $a <= 3; $a++) {
    for ($b = 1; $b <= 3; $b++) {
        if ($b == 2) {
            [1];
            [2] 2;
        }
        echo "$a,$b\n";
    }
}
?>

Drag options to blanks, or click blank then click option'

Acontinue

Bbreak

Cexit

Dreturn

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'break' instead of 'continue' which changes loop behavior.

Mixing 'break' and 'continue' incorrectly.

First continue; skips the inner loop iteration. Then continue 2; skips the outer loop iteration. Both use 'continue' with and without level.

5fill in blank

hard

Fill all three blanks to skip the current iteration of the innermost loop, then the middle loop, then the outer loop.

PHP

<?php
for ($i = 1; $i <= 3; $i++) {
    for ($j = 1; $j <= 3; $j++) {
        for ($k = 1; $k <= 3; $k++) {
            if ($k == 2) {
                [1];
                [2] 2;
                [3] 3;
            }
            echo "$i,$j,$k\n";
        }
    }
}
?>

Drag options to blanks, or click blank then click option'

Acontinue

Bbreak

Cexit

Dreturn

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'break' or 'exit' which exit loops instead of continuing.

Omitting the level number for multi-level continue.

Each blank uses 'continue' to skip the current iteration at different loop levels: innermost (no level), middle (level 2), and outermost (level 3).

Practice

1.

What does the continue statement do inside a loop in PHP?

easy

A. It skips the rest of the current loop iteration and moves to the next iteration.

B. It stops the entire loop immediately.

C. It restarts the whole program.

D. It pauses the loop for a moment.

Solution

1. Step 1: Understand the role of continue in loops

   The continue statement tells the loop to skip the remaining code in the current iteration.

2. Step 2: What happens after continue?

   The loop immediately moves to the next iteration, not stopping the entire loop.

3. Final Answer:

   It skips the rest of the current loop iteration and moves to the next iteration. -> Option A

4. Quick Check:

   continue skips current iteration [OK]

Hint: Remember: continue skips current iteration only [OK]

Common Mistakes:

• Thinking continue stops the whole loop
• Confusing continue with break
• Assuming continue pauses the program

2.

Which of the following is the correct syntax to skip the current iteration of the outer loop in nested loops using continue in PHP?

for ($i = 0; $i < 3; $i++) {
    for ($j = 0; $j < 3; $j++) {
        if ($j == 1) {
            // What continue statement skips outer loop iteration?
        }
    }
}

easy

A. continue 2;

B. continue 1;

C. continue;

D. continue 3;

Solution

1. Step 1: Understand nested loop levels

   There are two loops: outer ($i) and inner ($j). To skip outer loop iteration, we use continue 2;.

2. Step 2: Apply continue n; syntax

   continue 2; skips the current iteration of the second enclosing loop (outer loop).

3. Final Answer:

   continue 2; -> Option A

4. Quick Check:

   continue 2; skips outer loop iteration [OK]

Hint: Use continue n; where n = loop level to skip [OK]

Common Mistakes:

• Using continue without number skips inner loop only
• Using continue 1; which skips inner loop only
• Using continue 3; which is invalid here

3.

What will be the output of the following PHP code?

for ($i = 1; $i <= 3; $i++) {
    for ($j = 1; $j <= 3; $j++) {
        if ($j == 2) {
            continue 2;
        }
        echo "$i$j ";
    }
}

medium

A. 11 13 12 22 32

B. 11 21 31

C. 11 12 13 21 22 23 31 32 33

D. 11 13 21 23 31 33

Solution

1. Step 1: Analyze the nested loops and continue 2;

   When $j == 2, continue 2; skips the rest of the inner and outer loop iteration, moving to next $i.

2. Step 2: Trace output for each iteration

   For $i=1: $j=1 prints '11 ', $j=2 triggers continue 2; skips to $i=2.
   For $i=2: $j=1 prints '21 ', $j=2 triggers continue 2; skips to $i=3.
   For $i=3: $j=1 prints '31 ', $j=2 triggers continue 2; loop ends.

3. Final Answer:

   11 21 31 -> Option B

4. Quick Check:

   continue 2 skips outer loop iteration [OK]

Hint: continue 2 skips outer loop iteration immediately [OK]

Common Mistakes:

• Assuming continue 2 skips only inner loop
• Expecting all combinations printed
• Ignoring that continue 2 skips outer loop iteration

4.

Find the error in this PHP code snippet that tries to skip the outer loop iteration when $j == 2:

for ($i = 0; $i < 3; $i++) {
    for ($j = 0; $j < 3; $j++) {
        if ($j == 2) {
            continue 3;
        }
        echo "$i$j ";
    }
}

medium

A. The continue statement should be break 3; instead.

B. There is no error; the code runs fine.

C. The echo statement is inside the wrong loop.

D. Using continue 3; causes a fatal error because only 2 loops exist.

Solution

1. Step 1: Count the nested loops

   There are only 2 loops: outer ($i) and inner ($j).

2. Step 2: Check the continue level

   continue 3; tries to skip 3 levels, but only 2 exist, causing a fatal error.

3. Final Answer:

   Using continue 3; causes a fatal error because only 2 loops exist. -> Option D

4. Quick Check:

   continue n must not exceed loop depth [OK]

Hint: continue n; must not exceed nested loop count [OK]

Common Mistakes:

• Using continue with number larger than loop depth
• Confusing continue with break
• Ignoring PHP fatal error on invalid continue level

5.

You want to print all pairs (i, j) for i and j from 1 to 3, but skip printing pairs where j == 2 and also skip the entire outer loop iteration if i == 2. Which code snippet correctly uses continue with levels to achieve this?

hard

A. for ($i = 1; $i <= 3; $i++) {
if ($i == 2) continue;
for ($j = 1; $j <= 3; $j++) {
if ($j == 2) continue;
echo "($i,$j) ";
}
}

B. for ($i = 1; $i <= 3; $i++) {
for ($j = 1; $j <= 3; $j++) {
if ($j == 2) continue;
if ($i == 2) continue 2;
echo "($i,$j) ";
}
}

C. for ($i = 1; $i <= 3; $i++) {
for ($j = 1; $j <= 3; $j++) {
if ($i == 2) continue 2;
if ($j == 2) continue;
echo "($i,$j) ";
}
}

D. for ($i = 1; $i <= 3; $i++) {
for ($j = 1; $j <= 3; $j++) {
if ($i == 2 || $j == 2) continue 2;
echo "($i,$j) ";
}
}

Solution

1. Step 1: Understand the requirements

   Skip printing pairs where j == 2, and skip entire outer loop iteration if i == 2.

2. Step 2: Analyze each option

   for ($i = 1; $i <= 3; $i++) {
       if ($i == 2) continue;
       for ($j = 1; $j <= 3; $j++) {
           if ($j == 2) continue;
           echo "($i,$j) ";
       }
   }

   skips i == 2 outer loop correctly but skips j == 2 only in inner loop.
   

   for ($i = 1; $i <= 3; $i++) {
       for ($j = 1; $j <= 3; $j++) {
           if ($j == 2) continue;
           if ($i == 2) continue 2;
           echo "($i,$j) ";
       }
   }

   tries to continue 2 inside inner loop after j check, but order is wrong.
   

   for ($i = 1; $i <= 3; $i++) {
       for ($j = 1; $j <= 3; $j++) {
           if ($i == 2) continue 2;
           if ($j == 2) continue;
           echo "($i,$j) ";
       }
   }

   first skips outer loop iteration if i == 2 using continue 2;, then skips j == 2 in inner loop.
   

   for ($i = 1; $i <= 3; $i++) {
       for ($j = 1; $j <= 3; $j++) {
           if ($i == 2 || $j == 2) continue 2;
           echo "($i,$j) ";
       }
   }

   skips outer loop iteration if either i == 2 or j == 2, which is incorrect.

3. Final Answer:

   Option C correctly uses continue 2; to skip outer loop when i == 2 and continue to skip j == 2. -> Option C

4. Quick Check:

   Use continue 2; to skip outer loop inside inner loop [OK]

Hint: Place continue 2; before continue for inner loop skip [OK]

Common Mistakes:

• Skipping outer loop for wrong conditions
• Using continue 2; incorrectly for inner loop skip
• Combining conditions incorrectly causing wrong skips