CamelCase Method.js

/*
Description:
Write simple .camelCase method (camel_case function in PHP, CamelCase in C# or camelCase in Java) for strings. All words must have their first letter capitalized without spaces.

For instance:

"hello case".camelCase() => HelloCase
"camel case word".camelCase() => CamelCaseWord
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*/

String.prototype.camelCase=function(){
  let arg = this.toString().trim().split(' ');
  let arr = arg.map((v,i,arr)=>v?v.slice(0,1).toUpperCase()+v.slice(1):v);
  return arr.join('');
}