Undefined and how to initialiaze this var

Tell us what’s happening:
i am stock i need help with this pleaseeeeee

Your code so far


// Initialize these three variables
var a;
var b;
var c;

// Do not change code below this line

a = a + 1;
b = b + 5;
c = c + " String!";

var a=6;
var b=15;
 var ="I am a string!";

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/understanding-uninitialized-variables

Pay attention to the comments here. Your code also has a syntax error.

Let me know if this helps