taking care of the remaining classic divisions in combinat folder

src/sage/combinat/alternating_sign_matrix.py

@@ -1273,7 +1273,7 @@ def from_height_function(self,height):
             [ 1 -1  1]
             [ 0  1  0]
         """
-        return self.from_corner_sum(matrix( [[((i+j-height[i][j])/int(2))
+        return self.from_corner_sum(matrix( [[((i+j-height[i][j])//int(2))
                                               for i in range(len(list(height)))]
                                              for j in range(len(list(height)))] ))
 

src/sage/combinat/diagram_algebras.py

@@ -282,7 +282,7 @@ def check(self):
         """
         if self._base_diagram:
             tst = sorted(flatten(self._base_diagram))
-            if len(tst) % 2 != 0 or tst != range(-len(tst)/2,0) + range(1,len(tst)/2+1):
+            if len(tst) % 2 != 0 or tst != range(-len(tst) // 2,0) + range(1,len(tst) // 2+1):
                 raise ValueError("this does not represent two rows of vertices")
 
     def __eq__(self, other):
@@ -744,7 +744,7 @@ def __contains__(self, obj):
                 return False
         if len(obj.base_diagram()) > 0:
             tst = sorted(flatten(obj.base_diagram()))
-            if len(tst)%2 != 0 or tst != range(-len(tst)/2,0) + range(1,len(tst)/2+1):
+            if len(tst)%2 != 0 or tst != range(-len(tst)//2,0) + range(1,len(tst)//2+1):
                 return False
             return True
         return self.order == 0

src/sage/combinat/fully_packed_loop.py

@@ -490,7 +490,7 @@ def __init__(self, parent, generator):
             self._six_vertex_model = generator
 
         self.configuration = matrix(list(self._six_vertex_model))
-        self._n = len(self._end_point_dictionary)/2
+        self._n = len(self._end_point_dictionary) // 2
         Element.__init__(self, parent)
 
     def _repr_(self):
@@ -1204,30 +1204,30 @@ def _end_point_dictionary(self):
         for k in range(n):
             if k % 2 == 0:
                 # top row
-                end_points[1 + k/2] = (0, k)
+                end_points[1 + k // 2] = (0, k)
 
                 # bottom row
-                end_points[n + 1 + k/2] = (n-1, n-1-k)
+                end_points[n + 1 + k // 2] = (n-1, n-1-k)
 
         # sides for even case
         if n % 2 == 0:
             for k in range(n):
                 if k % 2 == 0:
                     # left side
-                    end_points[((3*n + 2 + k)/2)] = (n-1-k, 0)
+                    end_points[((3*n + 2 + k) // 2)] = (n-1-k, 0)
 
                     # right side
-                    end_points[(n + 2 + k)/2] = (k, n-1)
+                    end_points[(n + 2 + k) // 2] = (k, n-1)
 
         # side for odd case
         if n % 2 == 1:
             for k in range(n):
                 if k % 2 == 1:
                     # left side
-                    end_points[(3*n + 2 + k)/2] = (n-1-k, 0)
+                    end_points[(3*n + 2 + k) // 2] = (n-1-k, 0)
 
                     # right side
-                    end_points[(n + 2 + k)/2] = (k, n-1)
+                    end_points[(n + 2 + k) // 2] = (k, n-1)
 
         return end_points
 

src/sage/combinat/perfect_matching.py

@@ -834,7 +834,8 @@ def to_non_crossing_set_partition(self):
             raise ValueError("matching must be non-crossing")
         else:
             perm = self.to_permutation()
-            perm2 = Permutation([(perm[2*i])/2 for i in range(len(perm)/2)])
+            perm2 = Permutation([perm[2 * i] // 2
+                                 for i in range(len(perm) // 2)])
         return SetPartition(perm2.cycle_tuples())
 
 

src/sage/combinat/q_analogues.py

@@ -278,8 +278,8 @@ def q_binomial(n, k, q=None, algorithm='auto'):
         is_polynomial = isinstance(q, Polynomial)
 
     R = parent(q)
-    zero = R(0)
-    one = R(1)
+    zero = R.zero()
+    one = R.one()
 
     if not(0 <= k and k <= n):
         return zero
@@ -290,7 +290,7 @@ def q_binomial(n, k, q=None, algorithm='auto'):
     if algorithm == 'auto':
         from sage.symbolic.ring import SR
         if is_polynomial:
-            if n <= 70 or k <= n/4:
+            if n <= 70 or k <= n // 4:
                 algorithm = 'naive'
             else:
                 algorithm = 'cyclo_polynomial'
@@ -325,11 +325,12 @@ def q_binomial(n, k, q=None, algorithm='auto'):
         from sage.rings.polynomial.cyclotomic import cyclotomic_value
         return prod(cyclotomic_value(d,q)
                     for d in range(2,n+1)
-                    if (n/d).floor() != (k/d).floor() + ((n-k)/d).floor())
+                    if (n//d) != (k//d) + ((n-k)//d))
     elif algorithm == 'cyclo_polynomial':
         return prod(R.cyclotomic_polynomial(d)
                     for d in range(2,n+1)
-                    if (n/d).floor() != (k/d).floor() + ((n-k)/d).floor())
+                    if (n//d) != (k//d) + ((n-k)//d))
+
 
 def gaussian_binomial(n, k, q=None, algorithm='auto'):
     r"""

src/sage/combinat/ribbon_tableau.py

@@ -106,20 +106,20 @@ def length(self):
             sage: RibbonTableau([[1,0],[2,0]]).length()
             2
         """
-        if self.to_expr() == [[],[]]:
+        if self.to_expr() == [[], []]:
             return 0
 
         tableau = self.to_expr()[1]
         l = 0
         t = 0
         for k in range(len(tableau)):
-            t += len( [ x for x in tableau[k] if x is not None and x > -1 ] )
-            l += len( [ x for x in tableau[k] if x is not None and x > 0  ] )
+            t += len([ x for x in tableau[k] if x is not None and x > -1])
+            l += len([ x for x in tableau[k] if x is not None and x > 0])
 
         if l == 0:
             return t
         else:
-            return t/l
+            return t // l
 
     def to_word(self):
         """

src/sage/combinat/subword_complex.py

@@ -341,7 +341,7 @@ def upper_root_configuration(self):
         conf = self._root_configuration_indices()
         W = self.parent().group()
         Phi = W.roots()
-        N = len(Phi) / 2
+        N = len(Phi) // 2
         return [Phi[i - N] for i in conf if i >= N]
 
     # weights

src/sage/combinat/tiling.py

@@ -1479,8 +1479,8 @@ def _rows_mod_box_isometries(self, i):
 
         We test that there are four times less rows for that polyomino::
 
-            sage: len(T.rows()) / len(T._rows_mod_box_isometries(0))
-            4
+            sage: len(T.rows()) == 4 * len(T._rows_mod_box_isometries(0))
+            True
 
         Now, a real use case. A solution of the game Quantumino is a tiling
         of a 5x8x2 box. Since a 5x8x2 box has four orientation preserving