我下载NOIP的数据自己测发现没问题啊，可是Vijos说我WA……

program classroom;
type
tOrder=record
first:int64;
last:int64;
need:int64;
end;
var
limit:array[1..1000001] of int64;
orders:array[1..1000001] of tOrder;
day,size,i:longint;
first,last,mid:longint;
function error(last:integer):boolean;
var
i:longint;
now:int64;
num:array[1..1000001] of int64;
begin
for i:=1 to day+1 do
begin
num[i]:=0;
end;
for i:=1 to last do
begin
inc(num[orders[i].first],orders[i].need);
inc(num[orders[i].last+1],-orders[i].need);
end;
now:=0;
for i:=1 to day do
begin
inc(now,num[i]);
if now>limit[i] then
begin
exit(true);
end;
end;
exit(false);
end;

begin
assign(input,'classroom.in');
reset(input);
assign(output,'classroom.out');
rewrite(output);
readln(day,size);
for i:=1 to day do
begin
read(limit[i]);
end;
readln;
for i:=1 to size do
begin
readln(orders[i].need,orders[i].first,orders[i].last);
end;
first:=1;
last:=size+1;
while first<>last do
begin
mid:=(first+last) div 2;
if error(mid) then
begin
last:=mid;
end
else
begin
first:=mid+1;
end;
end;
if first=size+1 then
begin
writeln(0);
end
else
begin
writeln(-1);
writeln(first);
end;
close(input);
close(output);
end.