Let's consider the following code:
let arr = [];
for (let i = 0; i < 3; i++) {
arr[i] = []; // pay attention to this line
for (let j = 0; j < 3; j++) {
arr[i].push(j + 1);
}
}
console.log(arr);
An important place in this code is the creation
of an empty subarray. We can't omit this line,
because then in the inner loop, an attempt to
push data to arr[i]
will throw an error.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
for (let j = 1; j <= 5; j++) {
arr[i].push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
arr[i] = '';
for (let j = 1; j <= 5; j++) {
arr[i].push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
arr[i];
for (let j = 1; j <= 5; j++) {
arr[i].push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
arr[j] = [];
for (let j = 1; j <= 5; j++) {
arr[i].push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
arr = [];
for (let j = 1; j <= 5; j++) {
arr[i].push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.
The author of the following code wanted to make a two-dimensional array:
let arr = [];
for (let i = 0; i < 3; i++) {
arr[i] = [];
for (let j = 1; j <= 5; j++) {
arr.push(j);
}
}
console.log(arr);
The written code, however, does not do what it was intended. Find and correct the author's mistake.