Global Round 8 problem D reminds me of another problem, Global round 6 problem D as both are solved by constructive algorithms based on the technique of conservation of the total number of 1 bits and total balance respectively, followed by greedy distribution of the values to get the answer.

If anyone has seen more similar problems, kindly leave links in the comments. Thanks.

For this task on Atcoder,

from decimal import Decimal as dec
a,b = map(dec,input().split())
print(int(a*b))

gives AC, but

a,b = map(float,input().split())
print(int(a*b))

gives WA.

Why is it so? Thanks.

I have seen many pupils directly become experts after solving all the problems of the Div 4 contest. On the same contest, many specialists also solved all the problems but their rating did not change. Isn't it unfair to give out such massive rating changes in this contest?