JSFiddle - React, Tailwind, and code Playground

JavaScript

var twoDArray = [[9,1],[5,3],[4,2]];

twoDArray.sort(function(a, b){
    //Sort by first field
    return a[0] - b[0]; 
}); 

alert(JSON.stringify(twoDArray)); 

twoDArray.sort(function(a, b){
    //sort by second field
    return a[1] - b[1]; 
}); 

alert(JSON.stringify(twoDArray));