Assignment day6

Day6/conversation.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"fmt"
+	"sync"
+)
+
+/*
+1. Given a string containing conversation between alice and bob. In the string, if it reaches $, it means end of alice message and if it reaches #, it means end of bob's message. and if it reaches ^,
+it means end of conversation ignore string after that.
+
+Note: given string doesn't contain any spaces. If message contains two continuous conversations from one person it should be printed one after another as given in the example.
+
+write a program to separate out messages from alice and bob. Write messages from alice and bob on seperate channels, whenever a message from alice/bob, print it in front of their name as shown in the example below:
+
+Note: there is a single space before and after colon(:) and no space before and after comma.
+
+e.g: "helloBob$helloalice#howareyou?#Iamgood.howareyou?$^"
+output: alice : helloBob,bob : helloalice,bob : howareyou?,alice : Iamgood.howareyou?
+*/
+
+func main() {
+	var message string = "helloBob$helloalice#howareyou?#Iamgood.howareyou?$^"
+	aliceChannel := make(chan string)
+	bobChannel := make(chan string)
+	var wg sync.WaitGroup
+
+	// Index for start of new message.
+	var prevIndex int = 0
+
+	for i := 0; i < len(message)-1; i++ {
+
+		if message[i] == '$' {
+
+			// If alice talks
+			messageSlice := message[prevIndex:i]
+			wg.Add(1)
+
+			go func(i int) {
+				if i == len(message)-2 {
+					// End of conversation
+					fmt.Print("alice : ", <-aliceChannel)
+				} else {
+					fmt.Print("alice : ", <-aliceChannel, ",")
+				}
+				wg.Done()
+			}(i)
+
+			aliceChannel <- messageSlice
+			prevIndex = i + 1
+
+		} else if message[i] == '#' {
+
+			// If bob talks
+			messageSlice := message[prevIndex:i]
+			wg.Add(1)
+
+			go func(i int) {
+				if i == len(message)-2 {
+					// End of conversation
+					fmt.Print("bob : ", <-bobChannel)
+				} else {
+					fmt.Print("bob : ", <-bobChannel, ",")
+				}
+				wg.Done()
+			}(i)
+
+			bobChannel <- messageSlice
+			prevIndex = i + 1
+		}
+		wg.Wait()
+	}
+}

Day6/reserse_string.go

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+package main
+
+import (
+	"fmt"
+	"runtime"
+	"sync"
+)
+
+/*
+2. Given a string, reverse it using one go routine.And inside go routine print reversed string and number of goroutines launched
+
+e.g: Input: test123 output: 321tset 2
+*/
+
+func reverseString(message string, wg *sync.WaitGroup) {
+
+	rns := []rune(message)
+
+	for i, j := 0, len(rns)-1; i < j; i, j = i+1, j-1 {
+
+		rns[i], rns[j] = rns[j], rns[i]
+
+	}
+
+	fmt.Print(string(rns), " ")
+	wg.Done()
+}
+
+func main() {
+
+	var message string
+	fmt.Println("Enter string to reverse")
+	_, err := fmt.Scanf("%v", &message)
+	if err != nil {
+		fmt.Println("Invalid input string")
+		return
+	}
+
+	var wg sync.WaitGroup
+
+	wg.Add(1)
+	go reverseString(message, &wg)
+	numGoroutines := runtime.NumGoroutine()
+	wg.Wait()
+
+	fmt.Println(numGoroutines)
+}