Add concurrency

concurrency/cmd/csp/main.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"log"
+	"os"
+	"time"
+)
+
+type ZipTemp struct {
+	City        string
+	Latitude    string
+	Longitude   string
+	State       string
+	Temperature float64
+	Time        time.Time
+	ZipCode     string
+}
+
+func main() {
+	file, err := os.Open("./zipcodes-50.csv")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	// Set up channels.
+	var (
+		done   = make(chan struct{})
+		ztchan = make(chan *ZipTemp)
+		ttchan = make(chan []*ZipTemp)
+	)
+
+	// Start the rank and display goroutines.
+	go rank(ztchan, ttchan)
+	go display(ttchan, done)
+
+	// Process the CSV.
+	processCSV(file, ztchan)
+
+	// Wait for the last display output.
+	<-done
+}