please send solution for the below question

using System;
using System.Text;
using System.Runtime.InteropServices;

class Program
{
    [StructLayout(LayoutKind.Sequential)]
    internal struct PROCESS_INFORMATION
    {
        public IntPtr hProcess;
        public IntPtr hThread;
        public UInt32 dwProcessId;
        public UInt32 dwThreadId;
    }

    const UInt32 WAIT_OBJECT_0 = 0x00000000;
    const UInt32 INFINITE = 0xFFFFFFFF;

    [StructLayout(LayoutKind.Sequential)]
    internal struct SECURITY_ATTRIBUTES
    {
        public int nLength;
        public IntPtr lpSecurityDescriptor;
        public bool bInheritHandle;
    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct STARTUPINFO
    {
        public int cb;
        public IntPtr lpReserved;
        public IntPtr lpDesktop;
        public IntPtr lpTitle;
        public int dwX;
        public int dwY;
        public int dwXSize;
        public int dwYSize;
        public int dwXCountChars;
        public int dwYCountChars;
        public int dwFillAttribute;
        public int dwFlags;
        public short wShowWindow;
        public short cbReserved2;
        public IntPtr lpReserved2;
        public IntPtr hStdInput;
        public IntPtr hStdOutput;
        public IntPtr hStdError;
    }

    [DllImport("kernel32.dll", EntryPoint = "CreateProcess", CallingConvention = CallingConvention.Winapi, CharSet = CharSet.Auto, SetLastError = true)]
    static extern bool CreateProcess(string appName, StringBuilder cmdLine, IntPtr processAttr, IntPtr threadAttr, bool inheritHandles, int creationFlag, IntPtr environment, IntPtr curDir, ref STARTUPINFO startupInfo, ref PROCESS_INFORMATION processInfo);

    [DllImport("kernel32.dll", EntryPoint = "WaitForSingleObject", CallingConvention = CallingConvention.Winapi, SetLastError = true)]
    static extern UInt32 WaitForSingleObject(IntPtr hHandle, UInt32 timeOut);

    [DllImport("kernel32.dll", EntryPoint = "GetExitCodeProcess", CallingConvention = CallingConvention.Winapi, SetLastError = true)]
    static extern bool GetExitCodeProcess(IntPtr hHandle, out Int32 timeOut);

    [DllImport("kernel32.dll", EntryPoint = "CloseHandle", CallingConvention = CallingConvention.Winapi, SetLastError = true)]
    static extern bool CloseHandle(IntPtr hHandle);

    unsafe static void Main(string[] args)
    {
        PROCESS_INFORMATION pi = new PROCESS_INFORMATION();
        STARTUPINFO si = new STARTUPINFO();
        si.cb = Marshal.SizeOf(si);
        if (CreateProcess(@"C:\WINDOWS\notepad.exe", null /* parameter */, IntPtr.Zero, IntPtr.Zero, false, 0, IntPtr.Zero, IntPtr.Zero, ref si, ref pi))
        {
            uint result = WaitForSingleObject(pi.hProcess, INFINITE);
            if (result == WAIT_OBJECT_0)
            {
                Int32 returnCode;
                if (GetExitCodeProcess(pi.hProcess, out returnCode))
                    Console.Out.WriteLine(returnCode);
            }
            else
            {
                // error handler
            }

            CloseHandle(pi.hProcess);
            CloseHandle(pi.hThread);
        }
    }
}