// write your own find and findIndex function const arrNums = [20, 10, 2, 30, 60, 100, 1, 4, 5]; // find method const temp = 100; const findNum = (num) => { return num === temp; }; // find method return the number if availabe else return undefine if (arrNums.find(findNum)) { console.log("found"); } else { console.log("Not Found"); } // findIndexOf method // find index method return the index of this no if present else return -1 arrNums.findIndex(findNum); // (Hint: using for loop and if else) // ======================================================== // const practiceData = [ [14, 21, 23, 64], [33, 46, 51, 65], ]; const newArr = practiceData.map((each) => { return each.map((each) => { return each + 1; }); }); console.log(newArr); /** * requirement one * increment each number by one and output the resultant array using a higher order method and for loop * HINT: use nesting * solution = [[15,22,24,65], [34,47,52,66]] * * * requirement two * from the above array, create an array of array of even numbers using a higher order method and for loop * solution = [[14,64], [46]] */ const evenArray = practiceData.map((each) => { return each.filter((each) => { return each % 2 === 0; }); }); console.log(evenArray); // ======================================================== // const array = [23, 45, 467, 789, 34, 989, 56]; // problem => return an array such that numbers at odd idex are multiplied by 2 // and numbers at even index are multiplied by 10 const oddEven = array.map((each, index) => { return index % 2 ? each * 2 : each * 10; }); console.log(oddEven); // ======================================================== // const carBrands = ["honda", "toyota", "maruti", "tata"]; const carModel = ["city", "innova", "alto", "nano"]; const carObject = {}; for (let i = 0; i < carBrands.length; ++i) { carObject[carBrands[i]] = carModel[i]; } console.log(carObject); // using a higher order method, create a carObject variable such that /** * * { * honda:city, * toyota:innova, * maruti:alto, * tata:nano * } */ // ======================================================== // /** * Flattening Use the reduce method to “flatten” an array of arrays into a single array that has all the elements of the original arrays. // result = [1, 2, 3, 4, 5, 6] * * */ const arrays = [[1, 2, 3], [4, 5], [6]]; const newSingleArray = arrays.reduce((old, newA) => { return old.concat(newA); }); console.log(newSingleArray); // ======================================================== // /** * const countries = ['Finland', 'Denmark', 'Sweden', 'Norway', 'Iceland'] * return an array with all words converted into uppercase using higher order function * const countries = ['FINLAND', 'DENMARK', 'SWEDEN', 'NORWAY', 'ICELAND'] * * * */ const countries = ["Finland", "Denmark", "Sweden", "Norway", "Iceland"]; const countriesCapt = countries.map((country) => { return country.toUpperCase(); }); console.log(countriesCapt); // ======================================================== //