# 使用用户输入的数字总和4位数字[英] Sum of number using user entered 4 digit numbers

### 问题描述

```    using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Assignment_1
{
class Program
{
static void Main(string[] args)
{
string inputString;
int number;

{
//Title Text
Console.WriteLine("Cylinder - Surface area and volume calculator");

//Prompts for input request

Console.WriteLine("{0}", inputString);

Console.Write("Enter Height: ");
Height = double.Parse(inputString);

//displays user input for height

Console.WriteLine("{0}", inputString);

//Calculation and display of surface area

SurfaceArea = (((2 * ((3.149)) * Radius) + (((2 * (3.149)) * (Radius) * Height))));
Console.WriteLine("Surface Area = {0}", SurfaceArea);

//Calculation and display of volume

Console.WriteLine("The Volume = {0}", Volume);

}

//Prompt the user for a four digit number (e.g. 5297) and display the sum of all of the digits
//The four digit number must be read as a single number and the individual digits must be broken out using div (/) and mod (%).

Console.WriteLine("");

Console.WriteLine("Sum of the digits - enter four digit whole numbers");
Console.Write("please enter four digit whole number: ");
```

//在这一点9999我不是在要求答案，因为这是针对课堂的，但是某些指导会有所帮助

```            {
//Prompt the user for three numbers and display the largest number. Use Math.Max in your solution.
}
}
}
}
```

## 推荐答案

1. 您可以使用正则表达式:4位数字，[1..9]范围中的第一个数字
2. 您可以尝试parse 用户字符串进入int，如果解析成功，则在[1000..9999] range range

P.S.如您所要求的，我没有编码

### 问题描述

```    using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Assignment_1
{
class Program
{
static void Main(string[] args)
{
string inputString;
int number;

{
//Title Text
Console.WriteLine("Cylinder - Surface area and volume calculator");

//Prompts for input request

Console.WriteLine("{0}", inputString);

Console.Write("Enter Height: ");
Height = double.Parse(inputString);

//displays user input for height

Console.WriteLine("{0}", inputString);

//Calculation and display of surface area

SurfaceArea = (((2 * ((3.149)) * Radius) + (((2 * (3.149)) * (Radius) * Height))));
Console.WriteLine("Surface Area = {0}", SurfaceArea);

//Calculation and display of volume

Console.WriteLine("The Volume = {0}", Volume);

}

//Prompt the user for a four digit number (e.g. 5297) and display the sum of all of the digits
//The four digit number must be read as a single number and the individual digits must be broken out using div (/) and mod (%).

Console.WriteLine("");

Console.WriteLine("Sum of the digits - enter four digit whole numbers");
Console.Write("please enter four digit whole number: ");
```

// At this point i'm confused as to what i should do to get a 4digit number where the number cannot equal zero, be a decimal or be a negative number, cannot be less than 1000 or greater than 9999 i'm not asking for answers because this is for class but some guidance would be helpful

```            {
//Prompt the user for three numbers and display the largest number. Use Math.Max in your solution.
}
}
}
}
```

## 推荐答案

There're two simple ways to solve the problem:

1. You can use regular expressions: 4 digits, first one in [1..9] range
2. You can try parse user string into int, and if parsing succeeds, check if result within [1000..9999] range

P.S. As you've asked, I've refrained from coding