Added 2's complement

mathgenerator/funcs/__init__.py

@@ -71,3 +71,4 @@ from .multiplyComplexNumbersFunc import *
 from .geomProgrFunc import *
 from .geometricMeanFunc import *
 from .harmonicMeanFunc import *
+from .binary2sComplement import *

mathgenerator/funcs/binary2sComplement.py

@@ -0,0 +1,26 @@
+from  .__init__ import *
+
+def binary2sComplementFunc(maxDigits=10):
+    digits = random.randint(1, maxDigits)
+    question = ''.join([str(random.randint(0, 1)) for i in range(digits)]).lstrip('0')
+
+    answer = []
+    for i in question:
+        answer.append(str(int(not bool(int(i)))))
+
+    carry = True
+    j = len(answer) - 1
+    while j >= 0:
+        if answer[j] == '0':
+            answer[j] = '1'
+            carry = False
+            break
+        answer[j] = '0'
+        j -= 1
+
+    if j == 0 and carry == True:
+        answer.insert(0, '1')
+
+    problem = "2's complement of " + question + " ="
+    solution = ''.join(answer).lstrip('0')
+    return problem, solution