How to useSummation of First N Natural Numbers in Javascript
- Flatten the Matrix: Convert the 2D matrix into a 1D array to work with the numbers more easily.
- Calculate Expected Total: Determine the total sum of the first N natural numbers (1 to N), where N is the length of the flattened array plus one.
- Calculate Actual Sum: Iterate through the flattened array and compute the sum of its elements.
- Find the Missing Number: Subtract the actual sum from the expected total to find the missing number.
- Display the Result: Print the missing number to the console.
We know,
Sum of first n natural numbers is (n * (n + 1)) / 2;
Example: In this example, the code efficiently calculates and finds the missing number in a 2D matrix by comparing the expected and actual sums of the numerical sequence using JavaScript.
const matrix = [
[1, 2],
[4, 5],
[6, 8],
[7, 9]
];
const flattenedArray = matrix.flat();
const n = flattenedArray.length + 1;
const sumOfFirstN = (n * (n + 1)) / 2;
let sumOfArray = 0;
for (let i = 0; i < n - 1; i++) {
sumOfArray += flattenedArray[i];
}
const missingNumber = sumOfFirstN - sumOfArray;
console.log("Missing Number: ", missingNumber);
Output
Missing Number: 3
JavaScript Program to Find Missing Number in Matrix
You are presented with a two-dimensional matrix, matrix[][]
where each row contains an ordered sequence of positive integers. The task is to find the missing number in the matrix.
NOTE: Each row is a sequence of unique positive integers, arranged in ascending order.