未定义的错误。如何解决？
问题描述：
this is my program.When I run it, it gives the following error - a.sum undefined (type float32 has no field or method sum)
package main
import (
"fmt"
)
type Calculation interface {
operation(input []float32)
}
type Addition struct {
sum float32
}
func (a Addition) operation(input []float32) {
a.sum = input[0]
for _, a := range input[1:] {
a.sum += a
}
fmt.Println("Sum :", a.sum)
}
func main() {
var n int
fmt.Println("Enter the no of inputs : ")
fmt.Scanln(&n)
var input []float32
input = make([]float32 , n)
fmt.Println("Enter the numbers ")
for i:=0 ; i <n ; i++ {
fmt.Scanln(&input[i])
}
var c Calculation
i := Addition{0}
c = i
c.operation(input)
}
I have written 3 more functions Subtraction , Multiplication and Division with Addition. All of them follow similar format but those three run with out any error, Only addition is giving this error. Unable to figure out why.
答
Your variable a in the loop shadows the variable a representing Addition. Changing your loop to this will solve the problem:
for _, v := range input[1:] {
a.sum += v
}