C++ rand() each number only once

I need something like rand() but I want each number only once.

In example I have 10 ".txt" files that are named as numbers (1-10). I want to read what is inside there and cout it, but randomly.

I don't want 1.txt -> 2.txt -> 3.txt -> ... but something random like

5.txt -> 4.txt -> 1.txt -> ...

and each number should only come up once

Is there an "easy" way to do this?

string Path = "./Questions_Niko/" + random + ".txt"; 

There are several approaches. For example you can use standard algorithm std::random_shuffle declared in header <algorithm>

For example

#include <algorithm>
#include <iterator>

//...

int main()
{
   int a[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

   std::random_shuffle( std::begin( a ), std::end( a ) );

   for ( int i : a )
   {
      //  some stuff
   }
}

The other way is to use standard class std::bitset and set the corresponding bit in the set for already selected number.