# Modular inverse problem
Last edited: 2026-02-05
# Statement
Modular inverse problem
Given 2 $n$-bit integers $x, N \geq 0$ what is $x^{-1}$ mod $N$.
# Solutions
- Modular inverse algorithm (extended Euclidean algorithm)
- This has run time $O(n^3)$.
Last edited: 2026-02-05
Given 2 $n$-bit integers $x, N \geq 0$ what is $x^{-1}$ mod $N$.