# Kotlin – Nested For Loop

## Kotlin – Nested For Loop

In Kotlin, a nested for loop is a loop inside another loop. This allows you to iterate over elements in multiple dimensions, such as iterating over rows and columns in a matrix.

## Examples

### Example 1: Nested For Loop for Matrix

Let’s start with a simple example of using a nested for loop to iterate over elements in a matrix.

We’ll create a 2×3 matrix and print its elements using a nested for loop.

Kotlin Program

``````fun main() {
// Define the matrix
val matrix = arrayOf(
intArrayOf(1, 2, 3),
intArrayOf(4, 5, 6)
)

// Iterate over rows and columns using nested for loops
for (row in matrix) {
for (element in row) {
print("\$element ")
}
println()
}
}``````

Output

``````1 2 3
4 5 6 ``````

### Example 2: Nested For Loop for Multiplication Table

Another common use of nested for loops is to generate a multiplication table.

Here’s an example of generating a multiplication table up to 5×5.

Kotlin Program

``````fun main() {
// Generate a multiplication table using nested for loops
for (i in 1..5) {
for (j in 1..5) {
print("\${i * j} ")
}
println()
}
}``````

Output

``````1 2 3 4 5
2 4 6 8 10
3 6 9 12 15
4 8 12 16 20
5 10 15 20 25 ``````

## Summary

A nested for loop in Kotlin allows you to iterate over elements in multiple dimensions, such as iterating over rows and columns in a matrix or generating a multiplication table. It is a powerful tool for handling complex data structures and generating structured outputs.