C programming exercise

Write the code as follows ：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1
{
    class Program
    {
        static void Main(string[] args)
        {
            int k1 = 364;
            int k2 = 364;
            while (k1>=3)
            {
                k2+= k1 / 3;
                k1 = (k1 / 3) + (k1 % 3);
            }
            Console.WriteLine(" You can drink it altogether {0} A bottle of coke , be left over {1} Empty bottles ", k2, k1);


            Console.ReadKey(true);
            }
        }
    }

The program runs as follows ：

 

 

 

 

Write the code as follows ：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(" Please enter the string :");
            string str = Console.ReadLine();
            // Convert a string to an array of characters 
            char[] strArray = str.ToArray();

            // Loop traversal 
            for (int i = 0; i < strArray.Length; i++)
            {
                // Decide if it's a letter 
                if ((strArray[i] >= 'A' && strArray[i] <= 'Z') || (strArray[i] >= 'a' && strArray[i] <= 'z'))
                {
                    strArray[i] = (char)(strArray[i] + 3);
                    // Lowercase letters 
                    if (strArray[i] > 'z' && strArray[i] < 'z' + 4)
                    {
                        strArray[i] = (char)(strArray[i] - 26);//26 Is a total period 
                    }
                    // Capital 
                    if (strArray[i] > 'Z' && strArray[i] < 'Z' + 4)
                    {
                        strArray[i] = (char)(strArray[i] - 26);
                    }
                }

            }
            foreach ( char temp in strArray )
            {
                Console.Write(temp);
            }




                Console.ReadKey(true);
            }
        }
    }

The program runs as follows ：

 

 

Write the code as follows ：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1
{
    class Program
    {
        static void Main(string[] args)
        {
            // The user enters an ordered array 

            string str = Console.ReadLine();// Get user input    Separate... With spaces 
            string[] strArray = str.Split(' ');
            int[] intArray = new int[strArray.Length];// Define that the length of the number array is equal to that of the character array            
            for (int i = 0; i < strArray.Length; i++) // Get an array of numbers 
            {
                int number = Convert.ToInt32(strArray[i]);
                intArray[i] = number;
            }
            
           
            for(int j=0;j<intArray .Length -1;j++)// How many numbers, how many rounds （ length -1 Round is also ok , Because there are only numbers left in the end , There is no need to compare ）
            {
                // Compare 
                for(int i=0;i<intArray .Length -1;i++)// Compare and sort each number in the array 
                {
                    if(intArray [i]>intArray [i+1])
                    {
                        int temp = intArray[i];
                        intArray[i] = intArray[i +1];
                        intArray[i + 1] = temp;
                    }
                }
            }
            foreach (int temp in intArray )
            {
                Console.Write(temp + " ");
            }



            Console.ReadKey(true);
            }
        }
    }

The program runs as follows ：

 

 

Write the code as follows ：

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1
{
    class Program
    {
        static void Main(string[] args)
        {
            
            string str = Console.ReadLine();// Get user input    Separate... With spaces 
           string[] strArray= str.Split(' ');
            int[] intArray = new int[strArray.Length];// Define that the length of the number array is equal to that of the character array 
            // Get an array of numbers 
            for (int i=0;i<strArray .Length;i++)
            {
               int number= Convert.ToInt32(strArray [i]);
                intArray[i] = number;
            }
            int min=intArray [0];
            int minIndex = 0;
            for (int i=1;i<intArray .Length;i++)
            {
                if (intArray [i]<min)
                {
                    min = intArray[i];
                    minIndex = i;
                }
            }
            int t;
            t = intArray[0];
            intArray[0] = intArray[minIndex];
            intArray[minIndex] = t;

            foreach (int tep in intArray )
            {
                Console.Write(tep );
            }


                Console.ReadKey(true);
            }
        }
    }

The program runs as follows ：

 

Write the code as follows ：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1
{
    class Program
    {
        static void Main(string[] args)
        {
            

            // Judge whether it is a legal identifier    It consists of English letters and underscores   Cannot start with a number 
            string str = Console.ReadLine();
            bool pd = true;
          for(int i=0;i<str.Length;i++)
            {
                if ((str[i] < 'a' || str[i] > 'z') && (str[i] < 'A' || str[i] > 'Z') && (str[i] < '0' || str[i] > '9') && str[i] != '_')// Lowercase letters   Capital   Numbers    Underline 
                {
                    pd = false;
                    break;

                }
            }
          if(str[0]>='0'&&str[0]<='9')
            {
                pd = false;
            }
            if (pd )
                Console.WriteLine(" yes ");
            else
                Console.WriteLine(" No ");
            Console.ReadKey(true);
            }
        }
    }

The program runs as follows ：