ISAttack.sage

def ISAttack (R):
    R = ZZ(R)
    n = R.ndigits()
    #n = len(R)
    for j in range(1, n + 1):
        x=(R-(R % 10^j))/10^j
        p = gcd(x, R)
        if ((1 < p)and (p<R)):
            return(p)
    print "none found"