Easy Operators

Filter Even Numbers

Create a Flux emitting integers 1 through 10. Use the filter operator to keep only even numbers. Subscribe and print each on a new line.

filter() tests each element against a predicate, only passing through those that match.

Expected

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Main.kt

Filter Even Numbers

easy⏱ 15 minkotlinreactorchallengeoperators

Starter

Create a Flux emitting integers 1 through 10. Use the filter operator to keep only even numbers. Subscribe and print each on a new line.

filter() tests each element against a predicate, only passing through those that match.

Why this works

filter() evaluates a predicate for each element. Only elements where the predicate returns true are emitted downstream. Here, it % 2 == 0 keeps even numbers.

Expected output

Filter Even Numbers

Create a Flux emitting integers 1 through 10. Use the filter operator to keep only even numbers. Subscribe and print each on a new line.

filter() tests each element against a predicate, only passing through those that match.

Expected

2 4 6 8 10

Filter Even Numbers

easy⏱ 15 minkotlinreactorchallengeoperators

Starter

Create a Flux emitting integers 1 through 10. Use the filter operator to keep only even numbers. Subscribe and print each on a new line.

filter() tests each element against a predicate, only passing through those that match.

Why this works

filter() evaluates a predicate for each element. Only elements where the predicate returns true are emitted downstream. Here, it % 2 == 0 keeps even numbers.

Expected output

2 4 6 8 10