Distribute traffic by Making a biased toss to choose between ad networks in android?

Question

I have made an android app and I want to show exit ad. I have 3 ad networks. I want to pass a parameter from server to choose between these networks.

Lets say, I give edge to

adnetwork 1 = 50%
adnetwork 2, 40%
dnetwork 3, 10% 

and I want to distribute traffic in this order. That's it should allocate

50% traffic to adnetwork 1
40% to adnetwork 2
10% to adnetwork 3

I know about mediation networks but it doesn't work with adnetwork 1. So, I don't want to use ad mediation.

Answer 1

I found a solution to this problem, it works. I hope it helps someone else too.

 // Get a random number <= 100
 Random r = new Random();
 Integer n = r.nextInt(100);

 // Get the network allocations
 Integer allocation_network1 = 50;
 Integer allocation_network2 = 40;
 Integer allocation_network3 = 10;

 // Choose which network to use
 if (n <= allocation_network1) {
    // Display ad network1 Ad
 } 
 else if (n <= allocation_network1 + allocation_network2) {
    // Display ad network2 Ad

 } 
 else if (n <= allocation_network1 + allocation_network2 + allocation_network3){
 }