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Component and time complexity measures in terms of number of gates and gate delays, respectively, are derived for two multioperand adder structures: a tree of carry-save adders and a tree of carry-lookahead adders. The parameters of the complexity measures are operand length, number of operands, and maximum fanin to the gates. The analysis involves a constructive derivation of the complexity of carry-lookahead networks including optimization by removal of redundant paths. An alternate measure of component complexity, number of packages with a given number of pinouts, rather than number of gates, is also presented.