CareerCup

write a main program to take snapshots of VMs
Input: List of VMs(vmId: String), list of SLAs -> there is one-to-one mapping from VM to SLA

class SLA {
int freq_in_mins;
}

vm1 -> sla1{30 mins}
vm2 -> sla2{60 mins}

Constraints:
1) You can use takeSnapshot(vmId: String) -> Synchronous - I/O
2) If you start a snapshot of VM(with sla1) at time t0 and if it finishes at time t1, then the next snapshot should be scheduled at t1+sla1.freq_in_mins


vm1 at 00:00 and vm2 at 00:00
00:10 and 00:15

vm1 -> 00:10 + 30 = 00:40

write a class that 1) calculates the average of the stream, 2) provides an API read the average.

Handle overflows as the numbers can be very large and not fit into double/long.