i want to iterate for each crack size from 25 to 250mpa with 25 increments

I want to iterate for every load from 25 to 250 mpa with 25 increments but i didn't take conclusion. here my code and please help me;

clc
clear all
close all hidden
W = 0.4;
Sy = 250;
ea = 0.001;
Es = 0;
i=1;
fprintf('%10s      %10s       %10s\n','Load','K1eff Irwins app.','At iteration no');
for S = 25
    S = S+25;
    while abs(Es)<ea
        i=i+1;
        aold = 0.0254;
        x1 = aold/W;
        bold = 1+0.256.*x1-1.152.*x1.^2+12.2.*x1.^3;
        kold = bold.*S.*(pi.*aold).^1/2;
        rp = (1/(2.*pi)).*(kold./Sy).^(2);
        anew = aold + rp;
        x2 = anew./W;
        bnew = 1+0.256.*x2-1.152.*x2.^2+12.2.*x2.^3;
        knew = bnew.*S.*(pi.*anew).^(1/2);
        Es = abs((knew-kold)./knew).*100;
        if Es >= 0.0001
            anew = aold;
        end
    fprintf('%10.4f      %10.4f           [%10.4f]\n', S, knew, i)
    end

if S==250
    break
end
end

Answer 1

[Walter Roberson]

for S = 25 : 25 : 250

and get rid of the S=S+25 and the test for S==250

[Hasan]

I try but i can see only first load and i want to apply other load 25 increments each of them, I didn't success:(

Load K1eff Irwins app. At iteration no

25.0000 7.1665 [ 2.0000]