JSFiddle - React, Tailwind, and code Playground

by acturbo

JavaScript

console.clear();
var array1=    [21, 18];
var array2 =   [ [21, 1000], [21, 500], [18, 100], [18, 200] ];
var result =   [ [0,0], [0,0] ];

for (i=0;i<array1.length;i++){
    
	result[0,i][0] = array1[i];
	
	for (j=0;j<array2.length;j++){
        
        var key = array2[i,j][0];
        var val = array2[i,j][1];
        
        if (  key == array1[i] ){
            result[0,i][1] += val;
        }
	}
}

console.log( result );