Use Decimal in floats checker

dmoj/checkers/floats.py

@@ -1,3 +1,4 @@
+from decimal import Decimal
 from re import split as resplit
 
 from dmoj.error import InternalError
@@ -27,7 +28,13 @@ def verify_default(process_float, judge_float, epsilon):
             abs(1.0 - process_float / judge_float) <= epsilon)
 
 
-def check(process_output, judge_output, precision=6, error_mode='default', **kwargs):
+def check(process_output, judge_output, precision=6, fast=True, error_mode='default', **kwargs):
+
+    if fast:
+        float_datatype = float
+    else:
+        float_datatype = Decimal
+
     # Discount empty lines
     process_lines = list(filter(None, resplit(b'[\r\n]', utf8bytes(process_output))))
     judge_lines = list(filter(None, resplit(b'[\r\n]', utf8bytes(judge_output))))
@@ -44,7 +51,7 @@ def check(process_output, judge_output, precision=6, error_mode='default', **kwa
     if not verify_float:
         raise InternalError('invalid `error_mode` value')
 
-    epsilon = 10 ** -int(precision)
+    epsilon = float_datatype(10) ** -int(precision)
 
     try:
         for process_line, judge_line in zip(process_lines, judge_lines):
@@ -57,13 +64,13 @@ def check(process_output, judge_output, precision=6, error_mode='default', **kwa
             for process_token, judge_token in zip(process_tokens, judge_tokens):
                 # Allow mixed tokens, for lines like "abc 0.68 def 0.70"
                 try:
-                    judge_float = float(judge_token)
+                    judge_float = float_datatype(judge_token)
                 except ValueError:
                     # If it's not a float the token must match exactly
                     if process_token != judge_token:
                         return False
                 else:
-                    process_float = float(process_token)
+                    process_float = float_datatype(process_token)
 
                     if not verify_float(process_float, judge_float, epsilon):
                         return False