as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
design an algorithm to solve the following problem: given a nxn matrix, find the smallest positive integer missing from it.
user
a possible algorithm to solve the problem is as follows: 
1. initialize a result variable (res) to -1.
2. iterate over the given matrix.
3. for each element, check if it is greater than 0.
4. if so, store it in a set s.
5. for each element in the matrix, iterate from 1 to n and if the element is not present in the set, update the result variable (res) with the value and break from the loop.
6. finally, return res.
assistant