Operator precedence in Kotlin - Step-by-Step Execution

Concept Flow - Operator precedence

Start Expression

↓

Identify Operators

↓

Check Precedence

↓

Evaluate Highest Precedence Operator

↓

Replace with Result

↓

More Operators?

Yes→Repeat Check Precedence

No↓

Final Result

The program reads an expression, finds operators, evaluates them by precedence order, and repeats until the final result is computed.

Execution Sample

Kotlin

val result = 3 + 4 * 2
println(result)

Calculates 3 plus 4 times 2, showing how multiplication happens before addition.

Execution Table

Step	Expression	Operator Evaluated	Operation	Result
1	3 + 4 * 2	*	4 * 2	8
2	3 + 8	+	3 + 8	11
3	11	None	Final result	11

💡 No more operators left, final result is 11

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
result	undefined	undefined	undefined	11

Key Moments - 2 Insights

Why does multiplication happen before addition?

Because multiplication has higher precedence than addition, as shown in execution_table step 1 where '*' is evaluated before '+'.

What if we want addition first?

We use parentheses to change precedence, e.g. (3 + 4) * 2, which forces addition before multiplication.

Visual Quiz - 3 Questions

Look at the execution_table, what is the result after step 1?

A 6

B 8

C 11

D 14

💡 Hint

Check the 'Result' column in execution_table row for step 1.

At which step is the addition operator '+' evaluated?

A Step 1

B Step 3

C Step 2

D Never

💡 Hint

Look at the 'Operator Evaluated' column in execution_table.

If the expression was (3 + 4) * 2, what would be the final result?

A 14

B 11

C 10

D 8

💡 Hint

Parentheses change precedence, so addition happens first: 3+4=7, then 7*2=14.

Concept Snapshot

Operator precedence decides which operator runs first in expressions.
Multiplication (*) and division (/) have higher precedence than addition (+) and subtraction (-).
Use parentheses () to change the order.
Kotlin evaluates operators from highest to lowest precedence step-by-step.

Full Transcript

Operator precedence in Kotlin means some operations happen before others in an expression. For example, multiplication happens before addition. In the code 'val result = 3 + 4 * 2', Kotlin first calculates 4 times 2, then adds 3. This is because '*' has higher precedence than '+'. If you want addition first, use parentheses like '(3 + 4) * 2'. The execution table shows each step: first multiply, then add, then get the final result. Variables update only after all operations finish. Remember, parentheses can change the order to what you want.