$ perl solver.pl
x = 0 ; val = -8 ; temp = 2; step = 10
x = 0.000000000000000 val = -8.000000000000000 temp = 2.000000000000000 avg = 5.000000000000000
x = 5.000000000000000 val = -3.000000000000000 temp = 2.000000000000000 avg = 7.500000000000000
x = 7.500000000000000 val = -0.500000000000000 temp = 2.000000000000000 avg = 8.750000000000000
x = 7.500000000000000 val = -0.500000000000000 temp = 0.750000000000000 avg = 8.125000000000000
x = 7.500000000000000 val = -0.500000000000000 temp = 0.125000000000000 avg = 7.812500000000000
x = 7.812500000000000 val = -0.187500000000000 temp = 0.125000000000000 avg = 7.968750000000000
x = 7.968750000000000 val = -0.031250000000000 temp = 0.125000000000000 avg = 8.046875000000000
x = 7.968750000000000 val = -0.031250000000000 temp = 0.046875000000000 avg = 8.007812500000000
x = 7.968750000000000 val = -0.031250000000000 temp = 0.007812500000000 avg = 7.988281250000000
x = 7.988281250000000 val = -0.011718750000000 temp = 0.007812500000000 avg = 7.998046875000000
x = 7.998046875000000 val = -0.001953125000000 temp = 0.007812500000000 avg = 8.002929687500000
x = 7.998046875000000 val = -0.001953125000000 temp = 0.002929687500000 avg = 8.000488281250000
x = 7.998046875000000 val = -0.001953125000000 temp = 0.000488281250000 avg = 7.999267578125000
x = 7.999267578125000 val = -0.000732421875000 temp = 0.000488281250000 avg = 7.999877929687500
x = 7.999877929687500 val = -0.000122070312500 temp = 0.000488281250000 avg = 8.000183105468750
x = 7.999877929687500 val = -0.000122070312500 temp = 0.000183105468750 avg = 8.000030517578125
x = 7.999877929687500 val = -0.000122070312500 temp = 0.000030517578125 avg = 7.999954223632812
x = 7.999954223632812 val = -0.000045776367188 temp = 0.000030517578125 avg = 7.999992370605469
x = 7.999992370605469 val = -0.000007629394531 temp = 0.000030517578125 avg = 8.000011444091797
x = 7.999992370605469 val = -0.000007629394531 temp = 0.000011444091797 avg = 8.000001907348633
x = 7.999992370605469 val = -0.000007629394531 temp = 0.000001907348633 avg = 7.999997138977051
x = 7.999997138977051 val = -0.000002861022949 temp = 0.000001907348633 avg = 7.999999523162842
x = 7.999999523162842 val = -0.000000476837158 temp = 0.000001907348633 avg = 8.000000715255737
x = 7.999999523162842 val = -0.000000476837158 temp = 0.000000715255737 avg = 8.000000119209290
x = 7.999999523162842 val = -0.000000476837158 temp = 0.000000119209290 avg = 7.999999821186066
x = 7.999999821186066 val = -0.000000178813934 temp = 0.000000119209290 avg = 7.999999970197678
x = 7.999999970197678 val = -0.000000029802322 temp = 0.000000119209290 avg = 8.000000044703484
x = 7.999999970197678 val = -0.000000029802322 temp = 0.000000044703484 avg = 8.000000007450581
x = 7.999999970197678 val = -0.000000029802322 temp = 0.000000007450581 avg = 7.999999988824129
x = 7.999999988824129 val = -0.000000011175871 temp = 0.000000007450581 avg = 7.999999998137355
x = 7.999999998137355 val = -0.000000001862645 temp = 0.000000007450581 avg = 8.000000002793968
x = 7.999999998137355 val = -0.000000001862645 temp = 0.000000002793968 avg = 8.000000000465661
x = 7.999999998137355 val = -0.000000001862645 temp = 0.000000000465661 avg = 7.999999999301508
x = 7.999999999301508 val = -0.000000000698492 temp = 0.000000000465661 avg = 7.999999999883585
x = 7.999999999883585 val = -0.000000000116415 temp = 0.000000000465661 avg = 8.000000000174623
x = 7.999999999883585 val = -0.000000000116415 temp = 0.000000000174623 avg = 8.000000000029104
x = 7.999999999883585 val = -0.000000000116415 temp = 0.000000000029104 avg = 7.999999999956344
x = 7.999999999956344 val = -0.000000000043656 temp = 0.000000000029104 avg = 7.999999999992724
x = 7.999999999992724 val = -0.000000000007276 temp = 0.000000000029104 avg = 8.000000000010914
x = 7.999999999992724 val = -0.000000000007276 temp = 0.000000000010914 avg = 8.000000000001819
x = 7.999999999992724 val = -0.000000000007276 temp = 0.000000000001819 avg = 7.999999999997272
x = 7.999999999997272 val = -0.000000000002728 temp = 0.000000000001819 avg = 7.999999999999545
Result is: 8.0000000000