How to save the values of (x,C) in file 1 and (x,y) in file 2 to plot them in file 3.. the description in the code below

%  file 1
clc;
clear;
x=[1 3 2 5 8]
for i=1:10
    C=i*(x);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%
%  file 2
clc;
clear;
y=[2 3 1 6 8]
or i=1:10
    C=i*(x);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%
%  file 3
plot(x,C)
hold on
plot(y,C)

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[KSSV]

%  file 1
clc;
clear;
x=[1 3 2 5 8] ;
C = zeros(10,length(x)) ; 
for i=1:10
    C(i,:)=i*x;
end
writematrix(C,'file1.txt') ;
%%%%%%%%%%%%%%%%%%%%%%%%%%%
%  file 2
y=[2 3 1 6 8] ; 
C = zeros(length(y),10) ; 
for i=1:10
    C(i,:)=i*y;
end
writematrix(C,'file2.txt') ;
%%%%%%%%%%%%%%%%%%%%%%%%%%
%  file 3
C1 = importdata('file1.txt') ; 
x = data(:,1) ; 
C2 = importdata('file2.txt') ; 

y = data(:,1) ; 
plot(x,C1)
hold on
plot(y,C2)