C++ Random Number Generator [duplicate]

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• Why do I always get the same sequence of random numbers with rand()? 12 answers

I am trying to create a basic program in C++ that returns a random number each time the program is run. Very basic. But every time I run the program, I get the result

The random number selected was 41.

I have recompiled various times, but it makes no difference. My code is as follows:

#include <cstdlib>
#include <iostream>

using namespace std;

int main()
{
    float num = rand();
    cout<<"The random number selected was "<<num<<"\n";
    cin.get();

    return 0;
}

I use Dev-C++ as an IDE, but do not know my compiler, as when building the app, it simply says 'Default compiler'.

All answers (that are relevant) gladly appreciated!