Array transform algo doesnt seem to be right

Hello people…can you please help me with this problem

i understood the algo…
if there exists atleast n-1 numbers such that they can be reduced to 0 , then through some mathematical caluculations we deduce that there must be only 2 distinct remainders (number % k+1 ) and that only one or none of the numbers should give a different remainder…

But is it necessary that if there are two distinct remainders then the numbers can be deducted to zero?? how will u prove this??

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