Arrays are used to store multiple values in a single variable.
Each value is called an element, and each element has a numeric position in the array, known as its index.
Arrays are zero-indexed, meaning the first element is at index 0, the second at index 1, and so on.
Arrays can contain any data type, including numbers, strings, and objects.
const arr1 = [2, 4, 6]; array
arr1[0]; element at index 0 → 2
arr1[1]; element at index 1 → 4
arr1[2]; element at index 2 → 6
arr1[3]; element at index 3 → undefined index not found
Numbers are used to represent both integer and floating-point values.
Numbers are most commonly expressed in literal forms like 255 or 3.14159 ↴
let num1 = 5; → number
let num2 = 2.5; → number
let num3 = num1 + num2;
console.log(num3); returns ↴
7.5 → number
Find minimum number in an array using a for loop
for loop repeatedly executes a block of code until a specified condition evaluates to false.
The loop runs a block of code a set number of times, defined by an initialization, a condition, and an increment.
for (let x = 0; x < 4; x++) {
console.log(x);
}
Loop variable x is initialized to 0
Condition x < 4 is checked before each iteration.
The loop will continue to run as long as x is less than 4
The loop repeatedly executes a block of code 4 times, from 0 to 3
For each iteration of the loop, the current value of x is printed to the console.
After each iteration, x is incremented by 1 x++
When x reaches 4 the condition evaluates to false, terminating the loop.
0
1
2
3 → printed to console
Initialize an array from which to find the minimum number.
const array1 = [5, 8, 6, 4, 7]; → user input
Define a function findMinNumber to find minimum number.
function findMinNumber(arr) {}
The function takes an array as input arr and returns the smallest value found in that array.
Start with the first element as the minimum.
let min = arr[0] min
Iterate through arr starting from the second element.
for (let x = 1; x < arr.length; x++) {}
Check if current element arr[x] is less than the current minimum min
if (arr[x] < min) {}
Update min if the condition is true.
min = arr[x]
After the loop completes, return the minimum value found.
return min
Call the function with ↴
findMinNumber(array1);
Find the minimum number in an array.
arr = [5, 8, 6, 4, 7]
Loop through each number in the array.
for (let x = 1; x < arr.length; x++) {}
min = 5 start with first element as the minimum.
arr[x] = 8 start from second element.
arr[x] < min
Iteration ↴
1 8 < 5 false min = 5
2 6 < 5 false min = 5
3 4 < 5 true min = 4 min updated
4 7 < 4 false min = 4
Once the loop has completed the minimum number 4 is returned.
Find the minimum number in an array.
const array1 = [5, 8, 6, 4, 7];
function findMinNumber(arr) {
let min = arr[0];
for (let x = 1; x < arr.length; x++) {
if (arr[x] < min) {
min = arr[x];
}
}
return min;
}
call function
findMinNumber(array1); returns ↴
4
Alternative using built-in Math.min() method.
const arr = [5, 4, 6, 8, 7]; numbers only
Math.min(...arr); returns ↴
4