You don’t need a nested loop here. Just you one level for loop and use i as both the indices
var array1 = [1, 2, 3];
var array2 = [{word: "hey"}, {word: "hello"}, {word: "world"}]
for(let i = 0; i < array2.length; i++){
array2[i].id = array1[i];
}
console.log(array2);Cleaner way for doing this is to use map()
var array1 = [1, 2, 3];
var array2 = [{word: "hey"}, {word: "hello"}, {word: "world"}]
array2 = array2.map((x, i) => ({...x, id: array1[i]}));
console.log(array2);CLICK HERE to find out more related problems solutions.