⏱ 0:00est. 9 min

Merge Intervals

// https://github.com/6chinwei/rakuten-interview-test/blob/master/rakuten-interview-test.js
/*
Q3. Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). 
    You may assume that the intervals were initially sorted according to their start times. 
    Example 1: 
        Given intervals [1,3],[6,9], insert and merge [2,5] in as [1,5],[6,9]. 
    Example 2: 
        Given [1,2],[3,5],[6,7],[8,10],[12,16], insert and merge [4,9] in as [1,2],[3,10],[12,16]. 
        This is because the new interval [4,9] overlaps with [3,5],[6,7],[8,10].
*/

let input = [[1,3], [2,5], [6,9]];
input = [
    [3, 5], // min 3, max 5
    [1, 3],
    [7, 9]
]; // output [[1,5], [7,9]];
//let input = [[1,2],[3,5],[4,9],[6,7],[8,10],[12,16]]
let result = [];
let intervals = input.slice();
    intervals.sort((a, b) => a[0] - b[0]);

for (let i=0; i<intervals.length; i++) {
    if (intervals[i+1] && intervals[i+1][0] <= intervals[i][1]) {
        intervals[i+1][0] = Math.min(intervals[i+1][0], intervals[i][0]);
        intervals[i+1][1] = Math.max(intervals[i+1][1], intervals[i][1]);
    } else {
        result.push(intervals[i]);
    } 
}
console.log("********** SOL-3 ************")
console.log(result);

/**
Q1 Write a function that takes a string as input and returns the string reversed. 
   Please implement reverse function or method by yourself .
   Example: Given s = "hello", return "olleh"
**/

function reverse(str) {
    return str.split("").reverse().join("");
}

console.log("********** SOL-1 ************")
console.log(reverse("hello"))

/**
Q2. Given a positive integer num, write a function which returns True if num is a perfect square else False. 
    Note: Do not use any built-in library function such as sqrt. 
    Example 1: 
        Input: 16 
        Returns: True
**/

function isPerfectSquare(num) {
    for (i=1; i*i<=num;i++) {
        // if (i*i == num)
        if (num%i === 0 && num/i === i) {
            return true;
        }
    }

    return false;
}

console.log("********** SOL-3 ************")
console.log(isPerfectSquare(4));

/**
Q4. Given a 2D board and a word, find if the word exists in the grid. 
For example, 
Given board = 
[ 
  ['A','B','C','E'], 
  ['S','F','C','S'], 
  ['A','D','E','E'] 
] 
word = 'ABCCED', -> returns true, 
word = 'SEE', -> returns true, 
word = 'ABCB', -> returns false.
**/
var board = [ 
    ['A','B','C','E'], 
    ['S','F','C','S'], 
    ['A','D','E','E'] 
  ];

function isWordExisting(word) {
    var found = false;
    let n =3, m = 4;
    let i = 0, j = 0, k=0;
    while (i<n) {
        j=0;
        while(j<m) {
            k=0;
            if (board[i][j] === word[k]) {
                console.log(word[k]);
                k++;
                while(k<word.length-1) {
                    if (i+1 < n && j < m && board[i+1][j] === word[k]) {
                        console.log(word[k]);
                        i++;
                    } else if (i < n && j+1 < m && board[i][j+1] === word[k]) {
                        console.log(word[k]);
                        j++;
                    } else {
                        break;
                        // return false;
                    }
                    k++
                }
                if (found) {
                    return true;
                }
            }
            j++;
        }
        i++;
    }
    return false;
}

console.log("********** SOL-4 ************")
// console.log(isWordExisting('ABCCED'));
// console.log(isWordExisting('SEE'));
console.log(isWordExisting('ABCB'));