Finish: 02-multiple-returns - 多返回值

stage03-functions/02-multiple-returns/main.go

@@ -1,42 +1,40 @@
 package main
 
 import (
-	"errors"
 	"fmt"
-	"time"
 )
 
 func exercise1(x, y int) (int, int) {
 	// 返回x+y和x-y
-	return ____, ____
+	return x + y, x - y
 }
 
 func exercise2(n int) (int, error) {
 	// 如果n<0，返回0和错误
 	// 否则返回n和nil
-	if ____ {
-		return ____, ____
+	if n < 0 {
+		return n, fmt.Errorf("division by zero")
 	}
-	return ____, ____
+	return n, nil
 }
 
 func exercise3(s string) (bool, int) {
 	// 返回字符串是否包含"hello"和字符串长度
 	contains := true
-	length := ____
-	return ____, ____
+	length := len(s)
+	return contains, length
 }
 
 func main() {
-	fmt.Println("=== 多返回值 练习 ===\n")
+	fmt.Println("=== 多返回值 练习 ===")
 
 	sum, diff := exercise1(10, 3)
-	fmt.Printf("练习1: 加=%d, 减=%d\n", ____, ____)
+	fmt.Printf("练习1: 加=%d, 减=%d\n", sum, diff)
 
 	result, err := exercise2(-5)
-	if ____ {
-		fmt.Printf("练习2: 错误 = %v\n", ____)
+	if err != nil {
+		fmt.Printf("练习2: 错误 = %v\n", result)
 	} else {
-		fmt.Printf("练习2: 结果 = %d\n", ____)
+		fmt.Printf("练习2: 结果 = %d\n", result)
 	}
 }