function linearSearch(arr, target) {
for (let i=0; i<arr.length; ++i) {
if (arr[i]===target) {
return arr[i];
}
}
}
Binary Search
function binarySearchIterative(arr, target) {
let left = 0;
let right = arr.length-1;
while (left<=right) {
let mid = left + Math.floor((right-left)/2);
if (arr[mid]===target) {
return target;
}
if (target>arr[mid]) {
left = mid+1;
}
else {
right = mid-1;
}
}
return -1;
}
Sum From 1 to N
Iterative Search
function sumToNumber(n) {
let total = 0;
for (let i=1; i<=n; ++i) {
total+=i;
}
return total;
}
Single calculation/instruction
function sumtoNumber(n) {
return n*(n+1)/2;
}
Insert/Delete Item in an Array
function insert(arr, num) {
if (num>arr[arr.length-1]) {
arr[arr.length] = num;
return arr;
}
for (let i=0; i<arr.length;++i) {
if (num<=arr[i]) {
for (let j=arr.length;j>=i;j--) {
arr[j] = arr[j-1];
}
arr[i] = num;
break;
}
}
return arr;
}