6.Array Helper methods

//Array helper method
//finding a item from array
// looping array

//find
//filter
//every
//some
//findIndex
//map
//reduce

//works on array

//find
//must working on array
// must return something to get the result
//results a (single) the matched value based on condition
// const arr = [1, 3, 5, 7]

// const result = arr.find((elm) => elm === 10)

// console.log(result)

//filter
//must working on array
// must return something to get the result
//results a (single) the matched value based on condition
// const arr = [1, 3, 5, 7]

// const result = arr.filter((elm) => elm < 3)

// console.log(result)

//must working on array
// must return something to get the result
//results the index (single) matched value based on condition
// const arr = [1, 3, 5, 7]

// const result = arr.findIndex((elm) => elm === 3)

// console.log(result)

//must working on array
// must return something to get the result
//results an array having exact number of element(original source)
// const arr = [1, 3, 5, 7]

// const result = arr.map((elm) => elm * 3 )

// console.log(result)

//every
//must working on array
// must return something to get the result
//results an true or false based on condition
// const arr = [1, 3, 5, 7]

// const result = arr.every((elm) => elm > 0 )

// console.log(result)

//some
//must working on array
// must return something to get the result
//results an true or false based on condition
// const arr = [1, 3, 5, 7]

// const result = arr.some((elm) => elm > 10 )

// console.log(result)

//reduce
//must working on array
// must return something to get the result
//results depends what you want to do!

// 1 + 3 + 5 + 7
// const arr = [1, 3, 5, 7]
// // acc = 1, curr = 3  sum = 4
// // acc = 4 curr = 5 sum = 9
// // acc = 9 curr = 7 sum = 16

// const result = arr.reduce(
//   (acc, curr) => {
//     console.log(acc, curr)
//     return {
//       sum: acc.sum + curr,
//     }
//   },
//   {
//     sum: 10,
//   }
// )

// console.log(result)

// const arr = ['samim', 'Hasan']

// const result = arr.reduce((prevVal, currentVal) => {
//   return prevVal + ' ' + currentVal
// }, '')

// console.log(result)

//foreach
//doesn't return anything
// const arr = ['samim', 'Hasan']
// let resultStr = ''
//  arr.forEach((elm) => resultStr += elm)

// console.log(resultStr)

//slice doesn't modifies original array
//last index is exclusive

// const animals = ['ant', 'bison', 'camel', 'duck', 'elephant'];

// console.log(animals.slice(2, 4));
// console.log(animals)

//splice  modifies original array
//last index is inclusive
// const animals = ['ant', 'bison', 'camel', 'duck', 'elephant']

// console.log(animals.splice(2, 4))
// console.log(animals)