How do I extract the common elements from an array and put them into two arrays?

var arr = ["2018-04-17T03", "2018-04-18T15", "2018-04-17T04", "2018-04-18T16", "2018-04-17T05", "2018-04-18T17", "2018-04-17T06", "2018-04-17T07", "2018-04-17T08", "2018-04-17T09", "2018-04-17T20", "2018-04-18T10", "2018-04-17T21", "2018-04-18T11", "2018-04-17T00", "2018-04-17T22", "2018-04-18T12", "2018-04-17T01", "2018-04-17T23", "2018-04-18T13", "2018-04-17T02", "2018-04-18T14", "2018-04-17T14", "2018-04-18T04", "2018-04-17T15", "2018-04-18T05", "2018-04-17T16", "2018-04-18T06", "2018-04-17T17", "2018-04-18T07", "2018-04-17T18", "2018-04-18T08", "2018-04-17T19", "2018-04-18T09", "2018-04-17T10", "2018-04-18T00", "2018-04-17T11", "2018-04-18T01", "2018-04-17T12", "2018-04-18T02", "2018-04-17T13", "2018-04-18T03"];

The last three digits of each element in

arr are different. I want to intercept the first ten digits of each element into an array and put different ones into another array

Es6 javascript-array javascript
Mar.04,2021 
const arr = ["2018-04-17T03", "2018-04-18T15", "2018-04-17T04", "2018-04-18T16", "2018-04-17T05", "2018-04-18T17", "2018-04-17T06", "2018-04-17T07", "2018-04-17T08", "2018-04-17T09", "2018-04-17T20", "2018-04-18T10", "2018-04-17T21", "2018-04-18T11", "2018-04-17T00", "2018-04-17T22", "2018-04-18T12", "2018-04-17T01", "2018-04-17T23", "2018-04-18T13", "2018-04-17T02", "2018-04-18T14", "2018-04-17T14", "2018-04-18T04", "2018-04-17T15", "2018-04-18T05", "2018-04-17T16", "2018-04-18T06", "2018-04-17T17", "2018-04-18T07", "2018-04-17T18", "2018-04-18T08", "2018-04-17T19", "2018-04-18T09", "2018-04-17T10", "2018-04-18T00", "2018-04-17T11", "2018-04-18T01", "2018-04-17T12", "2018-04-18T02", "2018-04-17T13", "2018-04-18T03"];
const prefix = '2018-04-17';  // 
const samePrefix = []; // 
const others = []; // 
arr.forEach(date=>{
    if (date.substring(0,10) === prefix) {
        samePrefix.push(date)
    } else {
        others.push(date);
    }
})
var arr = ["2018-04-17T03", "2018-04-18T15", "2018-04-17T04", "2018-04-18T16", "2018-04-17T05", "2018-04-18T17", "2018-04-17T06", "2018-04-17T07", "2018-04-17T08", "2018-04-17T09", "2018-04-17T20", "2018-04-18T10", "2018-04-17T21", "2018-04-18T11", "2018-04-17T00", "2018-04-17T22", "2018-04-18T12", "2018-04-17T01", "2018-04-17T23", "2018-04-18T13", "2018-04-17T02", "2018-04-18T14", "2018-04-17T14", "2018-04-18T04", "2018-04-17T15", "2018-04-18T05", "2018-04-17T16", "2018-04-18T06", "2018-04-17T17", "2018-04-18T07", "2018-04-17T18", "2018-04-18T08", "2018-04-17T19", "2018-04-18T09", "2018-04-17T10", "2018-04-18T00", "2018-04-17T11", "2018-04-18T01", "2018-04-17T12", "2018-04-18T02", "2018-04-17T13", "2018-04-18T03"];
    const result=arr.reduce((obj,item)=>{
        const key=item.substring(0,10);
        if(!obj[key]){
            obj[key]=[];
        }
        obj[key].push(item);
        return obj;
    },{});
    const _result=Object.keys(result).map(key=>result[key]);
    console.log(_result);

Previous: How to dynamically add rows and dynamically calculate internal values in vue tables

Next: ReactNative version is low, JavaScript version is high, how to solve?

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b30685-2b55c.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b30685-2b55c.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?