a[0]:=maxsize；{maxsize 为maxlongint或-maxlongint}

for  i:=1 to n do

for j:=0 to i-1 do

if ( a[j]>a[i]) and (opt[j]+1>opt[i]) then

opt[i]:=opt[j]+1;

ans:=-maxlongint;

for i:=1 to n do

if opt[i]>ans then ans:=opt[i]; {ans 为最终解}