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// 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);
// ======================================================== //
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