输入三个数，将它们按从达到小的顺序排列

const n=3;
var a:array[1..n] of integer;
i,j,k,t:integer;
begin
write('Enter date:');
for i:= 1 to n do read(a[i]);
writeln;
for i:=1 to n-1 do
begin
k:=i;
for j:=i+1 to n do
if a[j]<a[k] then k:=j;
if k<>i then
begin t:=a[i];a[i]:=a[k];a[k]:=t;end;
end;
write('output data:');
for i:= 1 to n do write(a[i],' ');
writeln;
end.

选择排序。

program bj;
var a,b,c,max,min,mul:real;
begin
readln(a,b,c);
if a>b then max:=a
else max:=b;
min:=a+b-max;
if c>max then max:=c
else if c<min then min:=c;
mul:=a+b+c-max-min;
if (max-trunc(max)=0)and(mul-trunc(mul)=0)and(min-trunc(min)=0)
then write(trunc(max),' ',trunc(mul)' ',trunc(min))
else write(max,' ',mul,' ',min);
end.

此程序既适合整型，也适合实型

不用这么麻烦吧；
progra