How to find a minimum value without using min or specifically made functions

Question

function [c] = nextinteger(v)
c=0;
a =0;
h=[0];
for i= 1:length(v)
    if v(i)>0
        h=v;
        if h(i+1)>h(i)
            a = h(i);
            c=a+1;
        end 
    end
end
end

I have to "Write a function nextinteger(v) which takes as input a vector v and as output returns the smallest positive integer which does not appear in v ."

At the moment I cannot seem to find a solution and the code above is as far as I have got to the solution. Can someone tell me what I need to consider and what I need to fix to get closer to my solution

Example of desired outcome: If the input is

[1, 2, 3]

, the output would be

4

If the input is

[4, 0, 1, -10], 

the output would be

2

Answer 1

Example Input

v=[10 0 1 -1 3 4 5];

n=length(v); % length of input
tmp=1:n; % possible integer numbers
for k=1:n % loop over vector
    comp_value=v(k);

    for r=1:length(tmp) %loop over reference
        if tmp(r)==comp_value %compare 
           tmp(r)=[]; %eclude
           break
    end
    end
end

if isempty(tmp) % check whether all numbers are gone
    result=n+1;
else
    result=tmp(1);
end

output:

result =

 2