validation

2 resources tagged with validation.

Challenge

Build a Simple Password Strength Checker in Kotlin

Write a Kotlin function that evaluates a password and returns a clear strength label. You’ll validate input, apply a few practical rules, and practice string scanning in a way that mirrors real signup forms.

#kotlin#beginner#strings#validation#loops#conditionals

2/23/2026

Open resource

Challenge

Validate and Format Phone Numbers into E.164

Build a Kotlin function that takes a raw phone number string and converts it into a clean, standardized E.164-style format. You’ll handle common punctuation, validate the digits, and return either a formatted result or a clear error message.

#kotlin#strings#validation#functions#beginner#formatting

2/23/2026

Open resource

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