finished

src/test1.js

@@ -1,12 +1,17 @@
 function hello1(name) {
-  if(name){
+  if (name) {
     return 'hello ' + name
   }
   return 'Who are you?'
 }
 
 function hello2(firstname, lastname) {
   // TODO: Write code here
+  if (firstname) {
+    return `My name is ${firstname}${lastname ? ` ${lastname}` : ''}.`;
+  } else {
+    return `I have no firstname, but my lastname is ${lastname}.`;
+  }
 }
 
 module.exports = { hello1, hello2 };

src/test2.js

@@ -7,10 +7,15 @@ function multipleHello(number) {
 }
 
 function multipleTextByCharacter(text, selectedChar) {
-    /**
-     * count character in given text then multiple the text by that number 
-     */
-    // TODO: Write code here
+  /**
+   * count character in given text then multiple the text by that number 
+   */
+  // TODO: Write code here
+  let txt = "";
+  for (let i = 0; i < (text.match(new RegExp(selectedChar, "g")) || []).length; i++) {
+    txt += text;
+  }
+  return txt;
 }
 
 

src/test3.js

@@ -8,7 +8,11 @@ function spaceHello(number) {
   const hello = "hello";
   let text = "";
   for (let i = 0; i < hello.length; i++) {
-    text += hello[i] + space;
+    if (i === 0) {
+      text += hello[i];
+    } else {
+      text += space + hello[i];
+    }
   }
   return text;
 }

src/test4.js

@@ -11,20 +11,39 @@ function sumAbs(array) {
    * หาผลบวกของค่า absolute ของตัวเลขใน array
    */
   // TODO: Write code here
+  let res = 0;
+  for (const i of array) {
+    res += Math.abs(i);
+  }
+  return res;
 }
 
 function sumPositive(array) {
   /**
    * เลือกเฉพาะจำนวนบวกมาหาผลรวม ตอบผลรวมนั้น
    */
   // TODO: Write code here
+  let res = 0;
+  for (const i of array) {
+    if (i >= 0) {
+      res += i;
+    }
+  }
+  return res;
 }
 
 function maxAbsSum(array, maxNumber) {
   /**
    * เลือกเลขใน array มาไม่เกิน maxNumber ตัว ที่เอามา absolute แล้วได้ผลบวกเยอะสุด ตอบผลบวกนั้น
    */
   // TODO: Write code here
+  const arr = array.map(e => Math.abs(e));
+  arr.sort((a, b) => b - a);
+  let res = 0;
+  for (let i = 0; i < maxNumber; i++) {
+    res += arr[i];
+  }
+  return res;
 }
 
 module.exports = { sumSquare, sumAbs, maxAbsSum, sumPositive };

src/test5.js

@@ -1,5 +1,12 @@
 function checkPrime(number) {
   // TODO: write code here
+  let count = 0;
+  for (let i = 1; i <= number; i++) {
+    if (number % i === 0) {
+      count += 1;
+    }
+  }
+  return count === 2 ? true : false;
 }
 
 module.exports = { checkPrime };