Exercise 7 (Blogging Platform) Yerkibayev Zurab

exercise1/problem1/main.go

@@ -1,3 +1,19 @@
 package main
 
-func addUp() {}
+import (
+	"fmt"
+)
+
+func addUp(n int) int {
+	total := 0
+	for i := 1; i <= n; i++ {
+		total += i
+	}
+	return total
+}
+
+func main() {
+	fmt.Println(addUp(4))
+	fmt.Println(addUp(13))
+	fmt.Println(addUp(600))
+}

exercise1/problem10/main.go

@@ -1,3 +1,28 @@
 package main
 
-func sum() {}
+import (
+	"fmt"
+	"strconv"
+)
+
+func sum(a, b string) (string, error) {
+	num1, err1 := strconv.Atoi(a)
+	if err1 != nil {
+		return "", fmt.Errorf("string: %s cannot be converted", a)
+	}
+
+	num2, err2 := strconv.Atoi(b)
+	if err2 != nil {
+		return "", fmt.Errorf("string: %s cannot be converted", b)
+	}
+
+	result := num1 + num2
+
+	return strconv.Itoa(result), nil
+}
+
+func main() {
+	fmt.Println(sum("1", "2"))
+	fmt.Println(sum("10", "20"))
+	fmt.Println(sum("a", "2"))
+}

exercise1/problem2/main.go

@@ -1,3 +1,16 @@
 package main
 
-func binary() {}
+import (
+	"fmt"
+	"strconv"
+)
+
+func binary(decimal int) string {
+	return strconv.FormatInt(int64(decimal), 2)
+}
+
+func main() {
+	fmt.Println(binary(1))
+	fmt.Println(binary(5))
+	fmt.Println(binary(10))
+}

exercise1/problem3/main.go

@@ -1,3 +1,20 @@
 package main
 
-func numberSquares() {}
+import (
+	"fmt"
+)
+
+func numberSquares(n int) int {
+	sum := 0
+	for k := 1; k <= n; k++ {
+		sum += (n - k + 1) * (n - k + 1)
+	}
+	return sum
+}
+
+func main() {
+	fmt.Println(numberSquares(2))
+	fmt.Println(numberSquares(3))
+	fmt.Println(numberSquares(4))
+	fmt.Println(numberSquares(5))
+}

exercise1/problem4/main.go

@@ -1,3 +1,23 @@
 package main
 
-func detectWord() {}
+import (
+	"fmt"
+	"strings"
+)
+
+func detectWord(crowd string) string {
+	var result strings.Builder
+	for _, char := range crowd {
+		if char >= 'a' && char <= 'z' {
+			result.WriteRune(char)
+		}
+	}
+
+	return result.String()
+}
+
+func main() {
+	fmt.Println(detectWord("UcUNFYGaFYFYGtNUH"))
+	fmt.Println(detectWord("bEEFGBuFBRrHgUHlNFYaYr"))
+	fmt.Println(detectWord("YFemHUFBbezFBYzFBYLleGBYEFGBMENTment"))
+}

exercise1/problem5/main.go

@@ -1,3 +1,29 @@
 package main
 
-func potatoes() {}
+import (
+	"fmt"
+	"strings"
+)
+
+func potatoes(s string) int {
+	count := 0
+	substring := "potato"
+
+	for {
+		index := strings.Index(s, substring)
+		if index == -1 {
+			break
+		}
+		count++
+		s = s[index+len(substring):]
+	}
+
+	return count
+}
+
+func main() {
+	fmt.Println(potatoes("potato"))
+	fmt.Println(potatoes("potatopotato"))
+	fmt.Println(potatoes("potatoapple"))
+	fmt.Println(potatoes("potatopotatopotat"))
+}

exercise1/problem6/main.go

@@ -1,3 +1,33 @@
 package main
 
-func emojify() {}
+import (
+	"fmt"
+	"strings"
+)
+
+func emojify(sentence string) string {
+	emojis := map[string]string{
+		"smile": "🙂",
+		"grin":  "😀",
+		"sad":   "😥",
+		"mad":   "😠",
+	}
+
+	words := strings.Fields(sentence)
+
+	for i, word := range words {
+		cleanWord := strings.Trim(word, ",.!?;:")
+		if emoji, exists := emojis[cleanWord]; exists {
+			words[i] = strings.Replace(word, cleanWord, emoji, 1)
+		}
+	}
+
+	return strings.Join(words, " ")
+}
+
+func main() {
+	fmt.Println(emojify("Make me smile"))
+	fmt.Println(emojify("Make me grin"))
+	fmt.Println(emojify("Make me sad"))
+	fmt.Println(emojify("I am so mad!"))
+}

exercise1/problem7/main.go

@@ -1,3 +1,28 @@
 package main
 
-func highestDigit() {}
+import (
+	"fmt"
+	"strconv"
+)
+
+func highestDigit(num int) int {
+	numStr := strconv.Itoa(num)
+
+	highest := 0
+
+	for _, char := range numStr {
+		digit, _ := strconv.Atoi(string(char))
+
+		if digit > highest {
+			highest = digit
+		}
+	}
+
+	return highest
+}
+
+func main() {
+	fmt.Println(highestDigit(379))
+	fmt.Println(highestDigit(2))
+	fmt.Println(highestDigit(377401))
+}

exercise1/problem8/main.go

@@ -1,3 +1,27 @@
 package main
 
-func countVowels() {}
+import (
+	"fmt"
+	"strings"
+)
+
+func countVowels(s string) int {
+	vowels := "aeiou"
+	count := 0
+
+	s = strings.ToLower(s)
+
+	for _, char := range s {
+		if strings.ContainsRune(vowels, char) {
+			count++
+		}
+	}
+
+	return count
+}
+
+func main() {
+	fmt.Println(countVowels("Celebration"))
+	fmt.Println(countVowels("Palm"))
+	fmt.Println(countVowels("Prediction"))
+}

exercise1/problem9/main.go

@@ -1,7 +1,33 @@
 package main
 
-func bitwiseAND() {}
+import (
+	"fmt"
+)
 
-func bitwiseOR() {}
+func toBinary(n int) string {
+	return fmt.Sprintf("%08b", n)
+}
 
-func bitwiseXOR() {}
+func bitwiseAND(a, b int) int {
+	return a & b
+}
+
+func bitwiseOR(a, b int) int {
+	return a | b
+}
+
+func bitwiseXOR(a, b int) int {
+	return a ^ b
+}
+
+func main() {
+	a := 6
+	b := 23
+
+	fmt.Println("a =", toBinary(a))
+	fmt.Println("b =", toBinary(b))
+
+	fmt.Println("bitwiseAND =", toBinary(bitwiseAND(a, b)))
+	fmt.Println("bitwiseOR =", toBinary(bitwiseOR(a, b)))
+	fmt.Println("bitwiseXOR =", toBinary(bitwiseXOR(a, b)))
+}

exercise2/problem1/problem1.go

@@ -1,4 +1,22 @@
 package problem1
 
-func isChangeEnough() {
+import (
+	"fmt"
+)
+
+func isChangeEnough(change [4]int, amountDue float32) bool {
+
+	totalDueCents := int(amountDue * 100)
+
+	totalChangeCents := change[0]*25 + change[1]*10 + change[2]*5 + change[3]*1
+
+	return totalChangeCents >= totalDueCents
+}
+
+func main() {
+	fmt.Println(isChangeEnough([4]int{2, 100, 0, 0}, 14.11))
+	fmt.Println(isChangeEnough([4]int{0, 0, 20, 5}, 0.75))
+	fmt.Println(isChangeEnough([4]int{30, 40, 20, 5}, 12.55))
+	fmt.Println(isChangeEnough([4]int{10, 0, 0, 50}, 3.85))
+	fmt.Println(isChangeEnough([4]int{1, 0, 5, 219}, 19.99))
 }

exercise2/problem10/problem10.go

@@ -1,3 +1,37 @@
 package problem10
 
-func factory() {}
+import (
+	"fmt"
+)
+
+func factory() (map[string]int, func(string) func(int) int) {
+	brands := make(map[string]int)
+
+	makeBrand := func(brand string) func(int) int {
+
+		if _, exists := brands[brand]; !exists {
+			brands[brand] = 0
+		}
+
+		return func(count int) int {
+
+			brands[brand] += count
+			return brands[brand]
+		}
+	}
+
+	return brands, makeBrand
+}
+
+func main() {
+	brands, makeBrand := factory()
+
+	toyotaIncrementer := makeBrand("Toyota")
+	toyotaIncrementer(1)
+	toyotaIncrementer(2)
+	hyundaiIncrementer := makeBrand("Hyundai")
+	hyundaiIncrementer(5)
+	makeBrand("Kia")
+
+	fmt.Println(brands)
+}

exercise2/problem11/problem11.go

@@ -1,3 +1,26 @@
 package problem11
 
-func removeDups() {}
+import (
+	"fmt"
+)
+
+func removeDups[T comparable](items []T) []T {
+	seen := make(map[T]bool)
+	result := []T{}
+
+	for _, item := range items {
+		if !seen[item] {
+			seen[item] = true
+			result = append(result, item)
+		}
+	}
+
+	return result
+}
+
+func main() {
+
+	fmt.Println(removeDups([]int{1, 0, 1, 0}))
+	fmt.Println(removeDups([]bool{true, false, false, true}))
+	fmt.Println(removeDups([]string{"John", "Taylor", "John"}))
+}