Quantum Computing.
this problem to repeatedly squaring an integer, an algorithm also known as exponentiation by squaring. It turns out that if m is odd m^j = m (m²)^((j-1)/2) and if m is even m^j = (m²)^(j/2). For example let’s try j = 13 = 1101_2 in binary form. We need to multiply m by m² 6 times: ƒ = m m² = m³, ƒ