creating multiple objects with array of structures having unique random numbers - c++

Question

I am trying to create different objects, each with an array of structures of numbers with random values. After compiling I am getting the same sequence of number inside the arrays of every object.
Is there a way to create different objects with unique sequences of numbers inside the arrays?
#include <iostream>
#include <time.h>
#include <stdlib.h>
using namespace std;
struct storeTwoValue
{
int x;
int y;
};
class practice{
public:
storeTwoValue storageArray[10];
void valueGenerator()
{ srand(time(NULL));
for (int i = 0; i< 10; i++)
{
storageArray[i].x = rand()%10 +1;
storageArray[i].y = rand()%7 + 1;
}
}
void print()
{
cout<<"x"<<" "<<"y"<<endl;
for (int i = 0; i< 10; i++)
{
cout<<storageArray[i].x <<" ";
cout<< storageArray[i].y << endl;
}
cout<<endl;
}
};
int main()
{
for(int i=0; i<3; i++)
{ practice A;
A.valueGenerator();
A.print();
}
return 0;
}

Answer 1

Move the srand() call into main, i.e. execute it only once.
The way you are using it, it gets called in too short order for each object, at least if you create/initialise them all at start. I.e. they get all initialised while time(0) gives identical seeds, which means that the pseudo random number generator is basically reset (starting same sequence from same initial value).
To verify this, you can (before moving the srand call) extend your loop. If it takes enough time, so that time(0) reliably has different values, you will see groups of objects with same values within the groups, but different across groups.
Calling srand() should be done exactly once, calling it more often does not improve randomness.