I had a doubt regarding the codeforces rating change system since some time and it would be great if someone could help to clarify it.

Suppose there are 2 participants, A and B with A's rating less than B's rating. If participant A performs better or equal to the participant B, then it would be expected that participant A has more positive delta as compared to B since A was expected to perform worse but performed better or equal. But I have noticed previously in some cases and also in the recently held https://codeforces.me/contest/2127 that this is not the case.

Example:

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Could someone help with the confusion. Thanks a lot in advance!