done with the challange

dinho.js

@@ -0,0 +1,258 @@
+//html for code testing
+const sumOfNumber = document.querySelector(".sum-of-no");
+const lengthOfArr = document.querySelector(".len-of-arr");
+const totalItemsOfArr = document.querySelector(".len-of-arr");
+const NumOfChoice = document.querySelector(".num-of-choice");
+const firstAndLastName = document.querySelector(".first-and-last-name");
+const fiveLetterLong = document.querySelector(".five-letters-long");
+const addNameToArray = document.querySelector(".name-to-array");
+const countryWithAatTheEnd = document.querySelector(".country-with-a-at-end");
+const countryStartingWithN = document.querySelector(
+    ".country-with-starting-with-n"
+);
+const countryWithAInMiddle = document.querySelector(
+    ".country-with-a-in-middle"
+);
+
+
+//Array of numbers
+const arrOfNum = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+
+//======sum of numbers in an Array  (1(a)) SOLUTION=======
+const sumNub = arrOfNum.reduce((a, b) => {
+    return a + b;
+}, 0)
+//console.log(sumNub)
+
+//DOM for summation
+sumOfNumber.textContent = `= ${sumNub}`
+
+
+
+
+//=============Returning the total items in an array (1(b)) SOLUTION==========
+
+let counter = 0
+
+for (let i = 0; i < arrOfNum.length; i++) {
+    counter++;
+}
+
+const counted = counter
+
+// console.log(counter)
+
+//DOM for For counting numbers of items in an array
+lengthOfArr.textContent = `= ${counted}`
+
+//Alternatively with 'For___in Loop'
+let counting = 0
+
+for (i in arrOfNum) {
+    counting++
+}
+//console.log(counting)
+
+//Alternatively with '.LENGTH'
+const getNum = arrOfNum.length
+//console.log(getNum)
+
+
+
+
+//======Find number i want  (1(c)) SOLUTION=======
+const findNumFour = arrOfNum.find(four => four === 4)
+// console.log(findNumFour)
+
+//Alternatively
+const findNum = arrOfNum[3]
+//console.log(findNum)
+
+//DOM for Finding Number I want
+NumOfChoice.textContent = `= ${findNumFour}`
+
+
+
+
+
+
+
+
+
+
+
+//====== Finding first and last name in an array (2(a)) SOLUTION=======
+
+const arrOfName = ["Peter", "Paul", "Mary", "John", "Jane"];
+
+const findNam = arrOfName[0] + " and " + arrOfName[arrOfName.length - 1]
+
+//console.log(findNam)
+
+//DOM for getting first and last name
+firstAndLastName.textContent = `= ${findNam}`
+
+
+
+
+
+//====== Finding name of 5 letters long in an array (2(b)) SOLUTION=======
+
+const findFive = arrOfName.find(v => v.length == 5)
+// console.log(findFive)
+
+//Trying something
+const fiveLetter = arrOfName.map((x) => {
+    if (x.length == 5) {
+        return x
+    }
+})
+// console.log(fiveLetter)
+
+fiveLetterLong.textContent = `= ${findFive}`
+
+
+//====== Adding my name at the end of the array (2(b)) SOLUTION=======
+
+var addMyName = arrOfName.push("Dinho")
+//console.log(arrOfName)
+
+addNameToArray.textContent = `= ${arrOfName}`
+
+
+
+
+
+
+
+
+
+
+
+//====== Finding country starting with N in an array (3(a)) SOLUTION=======
+
+const arrOfCountry = ["USA", "UK", "Germany", "France", "Nigeria"];
+let findIt = arrOfCountry.find((x) => {
+    if (!x.indexOf("N"))
+        return x
+})
+//console.log(findIt)
+
+countryStartingWithN.textContent = `= ${findIt}`
+
+// var findN = arrOfCountry.map((x) => {
+//     if(!x.indexOf('N')){
+//         return x
+//     }
+// })
+
+// var findN = arrOfCountry.indexOf('Nigeria')
+
+// console.log(findN)
+
+// countryStartingWithN.textContent = findN
+
+
+//====== Finding an array of countries and returns the country that ends with the letter 'A' (3(b)) SOLUTION=======
+
+let findA = arrOfCountry.filter((x) => {
+    if (x[x.length - 1] == 'a' || x[x.length - 1] == 'A') {
+        return x
+    }
+})
+
+//console.log(findA)
+countryWithAatTheEnd.textContent = `= ${findA}`
+
+
+
+
+//====== Finding an array of countries and returns the country that has the letter 'a' in the middle. (3(c)) SOLUTION=======
+
+let findAMid = arrOfCountry.filter((x) => {
+    if (x[x.length - 1] !== 'a' && x[x.length - 1] !== 'A') {
+        if (x.includes('a')) {
+            return x
+        }
+    }
+})
+//console.log(findAMid)
+
+countryWithAInMiddle.textContent = `= ${findAMid}`
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+const arrOfObject = [
+    { name: "Peter", age: 30, country: "USA" },
+    { name: "Paul", age: 25, country: "UK" },
+    { name: "Mary", age: 28, country: "Germany" },
+    { name: "John", age: 35, country: "France" },
+    { name: "Jane", age: 28, country: "Nigeria" },
+];
+
+const countryWithMap = document.querySelector(
+    ".country-with-map");
+
+//======Finding an array of objects then loop through the array in 3 types of looping an array of objects. (4(a)) SOLUTION=======
+
+//first type, using map method to give the 'name' in the array of object
+
+let firstLoop = arrOfObject.map((x) => {
+    return x.name
+})
+//console.log(firstLoop)
+
+countryWithMap.textContent = `= ${firstLoop}`
+
+
+//second type, using filter method to filter an object with 'Paul' 
+let secondLoop = arrOfObject.filter((newName) => {
+    if (newName.name == 'Paul') {
+        return newName
+    }
+})
+console.log(secondLoop)
+
+
+//third type, using reduce method to sum the ages in 'age' object in the array 
+let thirdLoop = (items, prop)=>{
+    return items.reduce((newAge, score) => {
+            return newAge + score[prop]
+    },0)
+}
+
+console.log(thirdLoop(arrOfObject, 'age'))
+
+
+
+//function that takes an array of objects and returns the object that has age that is greater than 20 and less than 30.
+
+let findSomeAges = arrOfObject.filter((x) => {
+    if(x.age > 20 && x.age < 30){
+        return x
+    }
+})
+
+console.log(findSomeAges)
+
+//function that takes an array of objects and returns the object that has name that is 'John'.
+
+let findJohn = arrOfObject.filter((x) => {
+    if(x.name == 'John'){
+        return x
+    }
+})
+
+console.log(findJohn)