PASCAL循环求解

var
a: Array[1..20] Of longint;
i, j, t, n: Longint;
Begin
randomize;//启动随机发生器;
n := 20;
for i:=1 TO n Do a[i] := random(100);//随即一百个数
for i:=1 To n-1 Do//懒得写快排了，冒泡吧..
for j:=1 TO n Do
if a[i] < a[j] Then Begin
t := a[i]; a[i] := a[j]; a[j] := t;
End;
for i:=1 TO 20 DO Write(a[i], ' ');
End.

没有调试 直接写的，应该没有原则性错误...

program work;
var
a:array[1..20] of integer;
i,j,temp:integer;
begin
randomize;
for i:=1 to 20 do
a[i]:=random(100);

for i:=1 to 19 do
for j:=i+1 to 20 do
if a[j]>a[i] then
begin
temp:=a[i];
a[i]:=a[j];
a[j]:=temp;
end;
for i:= 1 to 20 do
write(a[i],' ');
end.

program sd;
var a:array[1..20]of integer;