created main.go to calculate total cost, rowsprocessed and timetaken

cur/karis/main.go

@@ -0,0 +1,122 @@
+package main
+
+// package cur
+// 1. The Worker (parseRow):
+// Create a function that takes one string (e.g., '1001 and a channel.
+// It must split the string and convert the price to a float64.
+// The Delay: Add time-Sleep(500 • time-Millisecond) to simulate real work,
+// 2. The Foreman (main):
+// Launch a Goroutine for every single row in the data slice.
+// use a Channel to collect the costs,
+// use a sync.WaitGroup to track when all workers are finished.
+// 3. The Goal:
+// Calculate the TotalCost and RowsProcessed.
+// Print the total time taken.
+
+import (
+	"encoding/csv"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+
+func parseRow(row string, costs chan<- float64, wg *sync.WaitGroup) {
+	defer wg.Done()
+
+	time.Sleep(500 * time.Millisecond)
+
+	parts := strings.FieldsFunc(row, func(r rune) bool {
+		return r == ',' || r == ' ' || r == '\t'
+	})
+	if len(parts) < 2 {
+		return
+	}
+
+	price, err := strconv.ParseFloat(parts[1], 64)
+	if err != nil {
+		return
+	}
+
+	costs <- price
+}
+
+func main() {
+	start := time.Now()
+
+	// Read CSV file 
+	file, err := os.Open("../testcur.csv")
+	if err != nil {
+		fmt.Println("Error opening testcur.csv:", err)
+		return
+	}
+	defer file.Close()
+
+	reader := csv.NewReader(file)
+
+	// Make a data slice of strings 
+	var data []string
+
+	for {
+		record, err := reader.Read()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			fmt.Println("Error reading CSV:", err)
+			return
+		}
+
+		if len(record) < 3 {
+			continue
+		}
+		//slicing 
+		id := strings.TrimSpace(record[0])
+		costStr := strings.TrimSpace(record[2])
+
+		if strings.EqualFold(id, "id") || strings.EqualFold(costStr, "cost") {
+			continue
+		}
+
+		// Send "id,cost"
+		data = append(data, id+","+costStr)
+	}
+
+	if len(data) == 0 {
+		fmt.Println("No valid rows found in testcur.csv.")
+		return
+	}
+
+	costs := make(chan float64)
+
+	var wg sync.WaitGroup
+	wg.Add(len(data))
+
+	for _, row := range data {
+		go parseRow(row, costs, &wg)
+	}
+
+	go func() {
+		wg.Wait()
+		close(costs)
+	}()
+
+	var totalCost float64
+	var rowsProcessed int
+
+	for cost := range costs {
+		totalCost += cost
+		rowsProcessed++
+	}
+
+	elapsed := time.Since(start)
+
+	fmt.Printf("RowsProcessed: %d\n", rowsProcessed)
+	fmt.Printf("TotalCost: %.2f\n", totalCost)
+	fmt.Printf("TotalTimeTaken: %s\n", elapsed)
+}
+