How to stop running code once conditions are met?

Hey guys, I'm trying to determine the average amount of people it would take to have two peopleh have the same birthday. Essentially I'm looking at the birthday paradox as an assignment for school. I haven't added the part where the function will run multiple times just yet. I'm still trying to figure out how to stop the program once two of the same number are rolled, store how many times that took, and then repeat for a thousand iterations. I know that this is probably not the best way to go about handling the code, but I'm having a hard time figuring out how else to go about it. I was thinking about using a while loop, but I don't know what the conditional statment would be.

function F = Birthday
% Birthday Paradox
%generates
%
% Outputs:
% Number of people before two people have the same birthday
%Created on:4/6/23
%Created by: M. Bruce

%Initialization

F = zeros(1,1000);

for n = 1:1000

    F(n) = randi(365);

    for k = 1:n-1
        if F(n) == F(n-k)
            break
        else
            return
        end
    end

end

Answer 1

[Walter Roberson]

  found_duplicate = false; 
  for k = 1:n-1
        if F(n) == F(n-k)
            found_duplicate = true;
            break
        end
  end
  if found_duplicate
      do the statistics stuff
  end

Answer 2

[James Tursa]

If your Birthday function is supposed to represent only one trial (a reasonable thing to do), then you should be returning n, not F. And when your inner for-loop finds a match, it needs to break out of both loops, not just the inner loop. E.g.,

% Some trials
for k=1:10
    Birthday
end

ans = 37

ans = 17

ans = 37

ans = 36

ans = 17

ans = 21

ans = 11

ans = 27

ans = 37

ans = 23

function n = Birthday % one trial of the birthday paradox
% Birthday Paradox
%generates
%
% Outputs:
% Number of people before two people have the same birthday
%Created on:4/6/23
%Created by: M. Bruce
%Initialization
F = zeros(1,365);
for n = 1:365
    F(n) = randi(365);
    for k = 1:n-1
        if F(n) == F(n-k) % could simply use F(k) here instead of F(n-k)
            return % done, so break out of both loops and return n
        end
    end
end
end

You can modify my "trials" loop to run a thousand trials, gather results, and generate statistics on these results.