bench compare C++ - Go

C++	GCC 10.2 -O3
-------------------------------------------------------
Benchmark             Time             CPU   Iterations
-------------------------------------------------------
Solve/10           83.5 ns         83.5 ns      9340607
Solve/100          1661 ns         1661 ns       426100
Solve/1000        24354 ns        24353 ns        27876
Solve/10000      304619 ns       304619 ns         2031
Solve/100000    3614361 ns      3614327 ns          192

Go go1.17.3
BenchmarkFence/10-8              9468015               116.4 ns/op
BenchmarkFence/100-8              690297              1901 ns/op
BenchmarkFence/1000-8              38958             30726 ns/op
BenchmarkFence/10000-8              2893            388989 ns/op
BenchmarkFence/100000-8              276           4883462 ns/op