代码在线执行—

package main

import (  
    "fmt"
)

// 定义一个接口
type SalaryCalculator interface {  
    CalculateSalary() int
}

type Permanent struct {  
    empId    int
    basicpay int
    pf       int
}

type Contract struct {  
    empId    int
    basicpay int
}

// 永久员工的薪资是 basicpay 与 pf 的和
func (p Permanent) CalculateSalary() int {  
    return p.basicpay + p.pf
}

// 合同工只有basicpay
func (c Contract) CalculateSalary() int {  
    return c.basicpay
}

// 通过迭代SalaryCalculator 切片，计算员工的薪资综合，从而计算出公司的总花费
func totalExpense(s []SalaryCalculator) {  
    expense := 0
    for _, v := range s {
        expense = expense + v.CalculateSalary()
    }
    fmt.Printf("每个月总花费： $%d", expense)
}

func main() {  
    pemp1 := Permanent{
        empId:    1,
        basicpay: 5000,
        pf:       20,
    }
    pemp2 := Permanent{
        empId:    2,
        basicpay: 6000,
        pf:       30,
    }
    cemp1 := Contract{
        empId:    3,
        basicpay: 3000,
    }
    employees := []SalaryCalculator{pemp1, pemp2, cemp1}
    totalExpense(employees)
}

运行结果 :