MATLAB: Replace spaces in a string

Question

Im doing a practice question and I got the question:

Replace any occurrence of two or more consecutive blank spaces with one (single) blank space

I attempted it a bunch of ways but so far the code Ive got is:

str = input('Enter a string: ');
[m, n] = size(str);
C = 0;
for i=1:n
    if str(i) == ' '
        C = C+1;
        blankpos(C) = i;
    end
end
fprintf('Position of the blank spaces: \n');
blankpos
C1 = 0;
strm=str;
for i=1:n
    if str == '   '
        C1 = C1+1;
        posreplace(C1)=i;
        if str == '  '
            C1 = C1+1;
            posreplace(C1)=i;
        end
    end
end
strm(posreplace) = ' ';
fprintf('The modified string: ');
strm

Answer 1

str = regexprep(str, ' +', ' ');