c++ code to shuffle the vlau in vecot r

// CPP program Illustrating the 
// use of random_shuffle 
#include <bits/stdc++.h> 
using namespace std; 
  
// random generator function 
int randomfunc(int j) 
{ 
    return rand() % j; 
} 
  
int main() 
{ 
    srand(unsigned(time(0))); 
    vector<int> arr; 
  
    // set some values: 
    for (int j = 1; j < 10; ++j) 
  
        // 1 2 3 4 5 6 7 8 9 
        arr.push_back(j); 
  
    // using built-in random generator 
    random_shuffle(arr.begin(), arr.end()); 
  
    // using randomfunc 
    random_shuffle(arr.begin(), arr.end(), randomfunc); 
  
    // print out content: 
    cout << "arr contains:"; 
    for (auto i = arr.begin(); i != arr.end(); ++i) 
        cout << ' ' << *i; 
  
    cout << endl; 
  
    return 0; 
}