Difference Between DWORD and Unsigned Int in C++

In C++, DWORD and Unsigned Int are commonly used data types to store non-negative integer values. Both the data types may appear similar but there are some important differences between them that the users should be aware of. In this article, we will learn the differences between DWORD and Unsigned int in C++.

DWORD Data Type in C++

• The DWORD data type is defined in the Windows API (Application Programming Interface) and is used to store non-negative integer values.

• It is commonly used when writing Windows applications or working with Windows-specific functions and structures.

• DWORD stands for "Double Word" and represents a 32-bit unsigned integer data type.

• DWORD variable can hold values in the range 0 to 4,294,967,295.

Unsigned Int Data Type in C++

• Unsigned int is a standard data type in C++ representing an unsigned integer value.

• The size of an unsigned int variable can vary depending on the specific compiler and platform being used.

• In most modern systems, unsigned int is typically a 32-bit or 64-bit data type.

• Unsigned int can store only positive values from 0 to 4,294,967,295.

Difference between DWORD and Unsigned Int in C++

Following are some key differences between DWORD and Unsigned int in C++:

C++ Program using DWORD

The following program illustrates the use of DWORD data type to display the current system time and system uptime in C++:

// C++ Program to show the current system time and uptime using DWORD in C++
#include <iostream>
#include <windows.h>
using namespace std;

int main()
{
    // Declare a SYSTEMTIME structure to hold the system
    // time
    SYSTEMTIME st;

    // Get the current system time
    GetSystemTime(&st);

    // Print the system time
    cout << "Current system time (UTC): " << st.wYear << "-"
         << st.wMonth << "-" << st.wDay << " " << st.wHour
         << ":" << st.wMinute << ":" << st.wSecond << "."
         << st.wMilliseconds << endl;

    // Use a DWORD variable to store the number of
    // milliseconds since system start
    DWORD uptime = GetTickCount();

    // Print the system uptime in milliseconds
    cout << "System uptime: " << uptime << " milliseconds"
         << endl;

    return 0;
}

Output:

Current system time (UTC): 2024-5-24 10:30:45.500
System uptime: 13255468 milliseconds

Time Complexity: O(1)
Auxiliary Space: O(1)

C++ Program using Unsigned Int

The following program illustrates the use of Unsigned int in C++:

// C++ Program using Unsigned Int
#include <iostream> 
using namespace std;

int main() 
{   
    // Declare an integer variable 'x' and initialize it with a value whichis larger than the maximum value an int can hold.
    int x = 4294967295;
    
    // This will result in an overflow
    cout << x << endl; 
    
    // Using unsigned it to store the same value and this will not result in an overflow
    unsigned int y = 4294967295; 
    cout << y << endl; 
}

-1
4294967295

Time Complexity: O(1)
Auxiliary Space: O(1)

Explanation: In the above example, we have used an unsigned int to store a value which is out of the range for int data type and prevented the overflow.