why I can't get s in this code ,who know matlab,help me? : I want to use t to calculate s,but i got error 

the code can't find S

[this is the logs][1] 

it's in chinese,the mean is can't find S,S is undefined.


    a=1;
    b=2;
    t=input('输入');
    
    if (-100<t<0) 
          T=t+100
          c1=20
          s=T*t
    end
    fprintf('输出%f\n',s)


THANKS!!

  [1]: https://i.stack.imgur.com/74VgM.png