const maxn=100005;
var ans,n,i,b:longint;
a:array[0..maxn] of longint;
begin
read(n,b);
for i:=1 to n do read(a[i]);
ans:=0;
repeat
ans:=a[i-1]+a[i];
until ans>n;
if ans>n then
begin
ans:=ans+a[i+1];
if ans>n then ans:=ans-a[i+1];
write(ans);
end;
end.
哪里错了