Random number within a range

Generating a random number in C++ is easy, but for generating one within a range you must use a little trick.

First, let’s see the script and then we shall analyze it.

// Generating a random number within a range

#include <windows.h>
#include <iostream>
using namespace std;

int main()
    int i = rand()%10;
    cout << i;
    return 0;
#include <windows.h>

-we must include ‘windows.h’ because we use GetTickCount().


-it retrieves the number of milliseconds elapsed since the system start. This is the trick for getting a random number. If we don’t use this function, we will get a random number, but the same number all the time. This is the way a computer creates a random number… the time.

int i = rand()%11; – this is the trick we use to get the number within a given range. We use the modulus operator to get the rest of the division of the number by eleven (because if we used %10 and the random number would be 10, 10%10 = 0).

Nathan Pakovskie is an esteemed senior developer and educator in the tech community, best known for his contributions to Geekpedia.com. With a passion for coding and a knack for simplifying complex tech concepts, Nathan has authored several popular tutorials on C# programming, ranging from basic operations to advanced coding techniques. His articles, often characterized by clarity and precision, serve as invaluable resources for both novice and experienced programmers. Beyond his technical expertise, Nathan is an advocate for continuous learning and enjoys exploring emerging technologies in AI and software development. When he’s not coding or writing, Nathan engages in mentoring upcoming developers, emphasizing the importance of both technical skills and creative problem-solving in the ever-evolving world of technology. Specialties: C# Programming, Technical Writing, Software Development, AI Technologies, Educational Outreach

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