How to detect the repetition of any number in a array?

Say a=[4 5 8 9 4], How to detect this set has repeated numbers? I do not want to know the number, I just want to know that "a set has repeated numbers or not"

Answer 1

[KSSV]

Check unique. If the length of your array and length of unique are not same it has repeated numbers.

a=[4 5 8 9 4] ;
b = unique(a) ;
if length(a)~=length(b)
    fprintf('array has repeated numbers\n')
else
    fprintf('array has no repeated numbers\n')
end

[Prasobhkumar P. P.]

Saved lots of hours of mine, thank you