洛谷 P1067 多项式输出

P1067 多项式输出

模拟，很坑的那种

var i,n:longint;     a:array[1..105] of integer;
begin
  readln(n);
  for i:=1 to n+1 do
    read(a[i]);
  if a[1]=-1
    then write('-');
  if a[1]<-1
    then write(a[1]);
  if (a[1]>1)
    then write(a[1]);
  if n=1 then write('x')
    else write('x^',n);
  for i:=2 to n do
  begin
    if a[i]=0 then continue;
    if a[i]=1
      then write('+')
      else
      if a[i]=-1
        then write('-')
        else
        begin
          if a[i]>0
            then write('+');
          write(a[i]);
        end;
    if n-i+1=1 then write('x')
    else write('x^',n-i+1);
  end;
  if a[n+1]<>0 then begin
  if a[n+1]>0
    then write('+');
  write(a[n+1]);
  end;
end.