Javascript-how to accumulate poll values when the code values of objects in the array are the same

Vararr [{code ...} vararr2 [{code...}]; how to implement the transformation from arr to arr1, and how to implement a similar transformation of var arr = [if the code value is not only abc but also adsdsddsda223 [

{"Code": "a", "poll": 7 },{ "code": "B", "poll": 2 },{ "code ": "c", "poll": 18 },{ "code": "a", "poll": 5 },{ "code": "c", "poll ": 12 },{ "code": "a", "poll": 1}];

Var arr2 = [

{"Code": "a", "poll": 13 },{ "code": "B", "poll": 2 },{ "code ": "c", "poll": 30}

];
How to implement the transformation from arr → to arr1, and how to implement a similar transformation if the code value is not only a B c, but also an arbitrary value of adsdsd dsdsd a223

Reply content:

Var arr = [

{"Code": "a", "poll": 7 },{ "code": "B", "poll": 2 },{ "code ": "c", "poll": 18 },{ "code": "a", "poll": 5 },{ "code": "c", "poll ": 12 },{ "code": "a", "poll": 1}];

Var arr2 = [

{"Code": "a", "poll": 13 },{ "code": "B", "poll": 2 },{ "code ": "c", "poll": 30}

];
How to implement the transformation from arr → to arr1, and how to implement a similar transformation if the code value is not only a B c, but also an arbitrary value of adsdsd dsdsd a223