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This is for 

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The algorithm is (men ~ patterns, women ~ terms):

    while ∃ free man m who still has a woman w to propose to {
       w = first woman on m’s list to whom m has not yet proposed
       if w is free
         (m, w) become engaged
       else some pair (m', w) already exists
         if w prefers m to m'
            m' becomes free
           (m, w) become engaged 
         else
           (m', w) remain engaged

This assumes that there are M patterns and N terms and that M = N. 
If M < N, there will not be a match unless there is a wildcard or a remainder (see their sections below) and we should short-circuit unless there is one.

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Is basically for free. We just run the algorithm for M (#patterns) <= N (#terms) and declare the result a match iff all patterns have a term assigned and there's at least one wildcard in the pattern list. E.g.

{ 1 | 2 | 3 } matches { 2 | _ | 1 | _ }

is matching N = 3 terms to a pattern list of M = 2 patterns and K = 2 wildcards, and the match will be successful.

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