implemented problem route

handlers.go

@@ -8,15 +8,31 @@ import (
 	"net/http"
 )
 
+type prob struct {
+	Operation string
+	First     int
+	Last      int
+}
+
 func attempt(w http.ResponseWriter, req *http.Request) {
 	operation := "+"
 	if r := rand.Intn(2); r == 0 {
 		operation = "-"
 	}
 
-	r := map[string]string{
-		"operation": operation,
+	first := rand.Intn(MAX)
+	var second int
+	if operation == "-" {
+		if first == 0 {
+			second = 0
+		} else {
+			second = rand.Intn(first)
 		}
+	} else {
+		second = rand.Intn(MAX)
+	}
+
+	r := prob{operation, first, second}
 
 	b, err := json.Marshal(r)
 	if err != nil {

main.go

@@ -9,6 +9,8 @@ import (
     "time"
 )
 
+const MAX = 12
+
 var addr = flag.String("addr", ":8000", "address I'll listen on.")
 var static_files = flag.String("static", "./static", "location of static files")