[WriteUp] / [CryptoHack - Elliptic Curves, Scalar Multiplication]

# Scalar multiplication on elliptic curve using double-and-add algorithm
def scalar_mult(k, P):
    result = None
    addend = P

    while k:
        if k & 1:
            result = point_add(result, addend)
        addend = point_double(addend)
        k >>= 1

    return result

# Given parameters
P = (2339, 2213)
k = 7863

# Calculate Q = k * P
Q = scalar_mult(k, P)

-> crypto{9467,2742}