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-Score calculators...
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+Internal term *score calculator* denotes algorithm, which is responsible for computing overall score (correctness) of a submitted solution from the results of individual solution test. Each exercise is given a calculator name and associated calculator configuration (stored in DB text column as Yaml), which is used to initialize/prepare the calculator before it is used for computing the score.
+
+We have implemented three calculators so far:
+
+## Uniform
+
+Trivial algorithm, which computes the overall score as arithmetic average of individual test scores. This calculator has no configuration.
+
+## Weighted
+
+Computes overall score as weighted average of individual test scores. The calculator expects that the weights are stored in the configuration in the following format:
+
+```
+testWeights:
+    "Test 01": 300
+    "Test 02": 200
+    "Test 03": 100
+```
+
+The keys are test names (must correspond with the `name` column of the `exercise_test`) and the values has to be integers.
+
+## Universal