为什么只得70分呀

program ex1;

var a:array[1..10000,1..5]of longint;

n,i,j,t:integer;

begin

readln(n);

for i:=1 to n do

begin

readln(a,a,a);

a:=a+a+a;

a:=i;

end;

for i:=1 to n-1 do

begin

for j:=i+1 to n do

begin

if(a