def dent(individual, lambda_=0.85):
 d = (lambda_ * exp((- ((individual[0] - individual[1]) ** 2))))
 f1 = ((0.5 * (((sqrt((1 + ((individual[0] + individual[1]) ** 2))) + sqrt((1 + ((individual[0] - individual[1]) ** 2)))) + individual[0]) - individual[1])) + d)
 f2 = ((0.5 * (((sqrt((1 + ((individual[0] + individual[1]) ** 2))) + sqrt((1 + ((individual[0] - individual[1]) ** 2)))) - individual[0]) + individual[1])) + d)
 return (f1, f2)

def dent ( individual , lambda_ = 0.85 ) : d = ( lambda_ * exp ( ( - ( ( individual [ 0 ] - individual [ 1 ] ) ** 2 ) ) ) ) f1 = ( ( 0.5 * ( ( ( sqrt ( ( 1 + ( ( individual [ 0 ] + individual [ 1 ] ) ** 2 ) ) ) + sqrt ( ( 1 + ( ( individual [ 0 ] - individual [ 1 ] ) ** 2 ) ) ) ) + individual [ 0 ] ) - individual [ 1 ] ) ) + d ) f2 = ( ( 0.5 * ( ( ( sqrt ( ( 1 + ( ( individual [ 0 ] + individual [ 1 ] ) ** 2 ) ) ) + sqrt ( ( 1 + ( ( individual [ 0 ] - individual [ 1 ] ) ** 2 ) ) ) ) - individual [ 0 ] ) + individual [ 1 ] ) ) + d ) return ( f1 , f2 )
test problem dent .