Arithmetic operators in Kotlin - Step-by-Step Execution

Concept Flow - Arithmetic operators

Start

↓

Evaluate operands

↓

Apply operator (+, -, *, /, %)

↓

Compute result

↓

Use result in expression or output

↓

End

This flow shows how Kotlin evaluates arithmetic expressions by first evaluating operands, then applying the operator to compute the result.

Execution Sample

Kotlin

fun main() {
  val a = 10
  val b = 3
  val sum = a + b
  val div = a / b
  println("sum = $sum, div = $div")
}

This code adds and divides two numbers, then prints the results.

Execution Table

Step	Expression	Operands	Operator	Result	Explanation
1	a = 10	-	-	10	Assign 10 to variable a
2	b = 3	-	-	3	Assign 3 to variable b
3	sum = a + b	10, 3	+	13	Add 10 and 3 to get 13
4	div = a / b	10, 3	/	3	Integer division of 10 by 3 gives 3
5	println	-	-	sum = 13, div = 3	Print the results
6	-	-	-	-	Program ends

💡 Program ends after printing the results.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	Final
a	-	10	10	10	10	10
b	-	-	3	3	3	3
sum	-	-	-	13	13	13
div	-	-	-	-	3	3

Key Moments - 2 Insights

Why does dividing 10 by 3 give 3 instead of 3.333?

Because both a and b are integers, Kotlin performs integer division which discards the decimal part. See step 4 in the execution_table.

What happens if we use + operator with two variables?

The + operator adds the values of the two variables. In step 3, a + b adds 10 and 3 to get 13.

Visual Quiz - 3 Questions

Look at the execution_table at step 3, what is the result of a + b?

A 13

B 30

C 7

D Error

💡 Hint

Check the 'Result' column in step 3 of the execution_table.

At which step does the program perform integer division?

A Step 2

B Step 4

C Step 5

D Step 3

💡 Hint

Look for the division operator '/' in the 'Operator' column.

If variable b was changed to 4, what would be the new result of a / b at step 4?

A 2.5

B 3

C 2

D 4

💡 Hint

Integer division truncates decimals; 10 / 4 equals 2 in integer division.

Concept Snapshot

Arithmetic operators in Kotlin:
- + addition
- - subtraction
- * multiplication
- / integer division (if both operands are Int)
- % modulus (remainder)
Operands are evaluated first, then operator applied.
Integer division discards decimals.

Full Transcript

This lesson shows how Kotlin uses arithmetic operators to calculate values. First, variables a and b are assigned 10 and 3. Then sum is calculated by adding a and b, resulting in 13. Next, div is calculated by dividing a by b using integer division, which results in 3 because decimals are discarded. Finally, the results are printed. Key points include understanding integer division and how operators work step-by-step.