Frequency, duplicates and missing number

About this topic

Count with arrays/hash and use sum tricks.

Part of Coding Tests: Pseudocode, Output Tracing & Patterns: 23 topics, 5 free.

More topics in this course

• How to dry-run code
• Reading company-test pseudocode
• Operator traps: ++, %, /, &&, bitwise
• Digit problems: reverse, palindrome, Armstrong
• Prime numbers and the sieve