operate

def oper(l, method="xor"):
    ops = {
      "xor" : "^",
      "or"  : "|", ## All maxed warning ##
      "and" : "&", ## All 0 warning ##
      "ls"  : "<<", ## Memory warning ##
      "rs"  : ">>",
      "mul" : "*",
      "sub" : "-",
      "add" : "+",
      "div" : "/",
      "mod" : "%", ## By 0 warning ##
      "exp" : "**" ## Time warning ##
    }
    a = l[:]
    for k1, v1 in enumerate(a):
        for k2, v2 in enumerate(a):
            exec("a[k1] {}= a[k2]".format(ops[method]))
    return a