Ошибки в программе о массивах

program one;
uses crt;
const n=22;
var
A:array [1..n] of integer;
b,i,j,max,min,x:integer;
flag:boolean;
BEGIN
clrscr;
randomize;
for i:=1 to n do
begin
a[i]:=random (50);
write (a[i], ' ');
end;
max:=a[1];
for i:=1 to n do
if a[i]>max
then max:=a[i];
writeln;
write ('maximalnii el-t massiva:', max);
min:=a[1];
for i:=1 to n do
if a[i]<min
then min:=a[i];
writeln;
write ('minimalnii el-t massiva:', min);
x:=a[min]; a[min]:=a[max]; a[max]:=x;
write (a[i], ' ');
end.

Uses
 crt;
const
 n=22;
var
 a:array [1..n] of integer;
 i,j,imax,imin,x:integer;
BEGIN
clrscr;
randomize;
imin:=1;
imax:=1;
for i:=1 to n do
begin
 a[i]:=random (50)-10;
 write (a[i], ' ');
 if a[i]>a[imax] then imax:=i;
 if a[i]<a[imin] then imin:=i;
end;
writeln;
write ('MAX[',imax,']:=',a[imax],'; MIN[',imin,']:=',a[imin]);
writeln;
x:=a[imin];
a[imin]:=a[imax];
a[imax]:=x;
for i:=1 to n do
 write(a[i], ' ');
readkey
end.