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const
n=5;
var
a:array[1..n,1..n] of integer;
i,j,s:integer;
begin
s:=0;
randomize;
for i:=1 to n do
begin
for j:=1 to n do
begin
a[i,j]:=random(10);
write(a[i,j]:4);
if (i+j) mod 3=0 then
s:=s+a[i,j];
end;
writeln;
end;
writeln('S=',s);
end.