number of threads is 1
Thread ID is 2
Thread ID is 16
Thread ID is 6
Thread ID is 7
Thread ID is 4
Thread ID is 11
Thread ID is 10
Thread ID is 9
Thread ID is 1
Thread ID is 0
Thread ID is 12
Thread ID is 15
single thread is 1
Thread ID is 3
Thread ID is 8
Thread ID is 5
Thread ID is 13
master threads is 0
Thread ID is 14
Thread ID is 17
Thread ID is 18
Thread ID is 19
sequential reduction time is 0.047226, value is 100000000




hand-rolled parallel reduction time is 0.009131, value is 100000000




OMP reduction time is 0.007833, value is 100000000




sum from 1 to 100000000 is 17.760059
sum from 100000000 to 1 is 18.000538