haskell - Summing a list of tuples -


i have list of tuples containing intergers.

[(123,123,123),(123,123,123),(123,123,123)]

i want sum of second values of list eg;

[(_,123,_),(_,123,_),(_,123,_)]

123 + 123 + 123

i think should using fold im not sure

extract second value list of tuple list new list , sum new list.

prelude> let = [(123,123,123),(123,123,123),(123,123,123)] prelude> sum [i | (_,i,_) <- a]

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