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console.log(missingNumber_2([1]));
console.log(missingNumber_2([0,1]));
console.log(missingNumber_2([9,6,4,2,3,5,7,0,1]));
// ChatGPT
function missingNumber_1(nums) {
// Create an array of numbers from 0 to the length of `nums`
let fullRange = Array.from({length: nums.length + 1}, (_, i) => i);
// Find the difference between the two arrays
let diff = fullRange.filter(x => !nums.includes(x));
// Return the first element of the resulting array
return diff[0];
}
// ChatGPT
function missingNumber_2(nums) {
// Sort the input array in ascending order
nums.sort(); // (a,b) => a-b
// Get the number of elements in the array
const count = nums.length;
// Loop through the elements in the array
for (let i = 0; i < count; i++) {
// Check if the current value is not equal to the loop variable "i"
if (nums[i] !== i) {
// If not, return "i" as the missing number
return i;
}
}
// If no missing number is found, return the length of the array
return count;
}
// ChatGPT
function missingNumber_3(nums) {
// Get the count of elements in the input array
const count = nums.length;
// Create an array with a range of numbers from 0 to count
const range = Array.from({ length: count+1 }, (_, i) => i);
// Loop through the elements of the range array
for (let num of range) {
// Check if the current number is not in the input array
if (!nums.includes(num)) {
// Return the first missing number
return num;
}
}
}
// ChatGPT
function missingNumber_4(nums) {
// Get the number of elements in the input array
const count = nums.length;
// Create an array of numbers from 0 to the count of elements in the input array
const range = Array.from({ length: count + 1 }, (_, i) => i);
// Calculate the sum of the range array
const rangeSum = range.reduce((acc, cur) => acc + cur, 0);
// Calculate the sum of the input array
const numsSum = nums.reduce((acc, cur) => acc + cur, 0);
// Return the difference between the two sums as the missing number
return rangeSum - numsSum;
}
// ChatGPT
function missingNumber_5(nums) {
// Create an array of the same size as the input array with all elements set to 0
const helper = Array.from({ length: nums.length + 1 }, () => 0);
// Loop through the elements of the input array
for (const num of nums) {
// Set the corresponding element in the helper array to 1
helper[num] = 1;
}
// Loop through the elements of the helper array
for (let i = 0; i < helper.length; i++) {
// Return the index of the first 0 in the helper array
if (helper[i] === 0) return i;
}
}
Also see: Tab Triggers