rt
本蒟蒻的代码
var n,i,j,i1,k,ans:longint;
p:boolean;
a:array[1..1010]of longint;
s:string;
begin
readln(n);
for i:=1 to n do read(a[i]);
for i:=1 to n-1 do
for j:=i+1 to n do
begin
k:=a[i]*a[j];
str(k,s);
p:=true;
for i1:=1 to length(s)-1 do if ord(s[i1])+1<>ord(s[i1+1]) then p:=false;
if (p) and (k>ans) then ans:=k;
end;
if ans<>0 then write(ans) else write(-1);
end.
原题中的数据点都对了,但就是错了。。。。