PROGRAMMING:Nested calls to functions

Find the sum of the largest and the smallest of the three numbers. Requirements: write three functions; A function to find the maximum of three numbers; Another function is to find the minimum of three numbers; The third function calls the first two functions to achieve the sum of the maximum number and the minimum number.
###Input format:
Assign values to three variables.
###Output format:
Output the sum of the maximum number and the minimum number. Output in the format of "MAX + min =".
###Input example:
```in
1 -24 20
```
###Output example:
```out
Max+Min=-4
```







answer：If there is no answer, please comment