require 'complex'
a = Complex(1.0, 2.0)
b = Complex(3.0, 4.0)
c = Complex(1, 2)
d = Complex(3, 4)
print "a ", a, " b ", b, " c ", c, " d ", d, "\n"
# => a 1.0+2.0i b 3.0+4.0i c 1+2i d 3+4i
print a + b, " ", a - b, " ", a * b, " ", a / b, "\n"
# => 4.0+6.0i -2.0-2.0i -5.0+10.0i 0.44+0.07999999999999999i
print c + d, " ", c - d, " ", c * d, " ", c / d, "\n"
# => 4+6i -2-2i -5+10i 11/25+2/25i
print 2 + b, " ", 2 - b, " ", 2 * b, " ", 2 / b, "\n"
# => 5.0+4.0i -1.0-4.0i 6.0+8.0i 0.24-0.32i
print a + 2, " ", a - 2, " ", a * 2, " ", a / 2, "\n"
# => 3.0+2.0i -1.0+2.0i 2.0+4.0i 0.5+1.0i