Simple frequency dict benchmarks

Here there be descriptions and test results. Eventually.

In the meantime, here's a cookie, and a test file: https://yadi.sk/d/xTFWy38y3GBAgS

pg.txt, 336 183 276 bytes, MD5 9ca4282866bb919e03cca2ed2b6ce429

Benchmark results

i5-4690 @ 3.7 GHz, Windows 7 x64

min..max	MB/s	program	compiler or runtime
1.310..1.325s	256.6	freq03.cpp	vs2019 16.1.0
1.747..1.778s	192.5	freq02.cpp	vs2019 16.1.0
2.462..2.491s	136.6	freq01.cpp	vs2019 16.1.0
2.655..2.675s	126.6	freq01.rs	rustc 1.43.1
4.397..4.512s	76.5	freq01.go	go 1.14.1
30.973..31.318s	10.9	freq01.php	php 7.0.20-zts
99.880..102.353s	3.4	freq01.py	python 3.7.0
1.407..1.416s	239.0	hack01.cpp	vs2019 16.1.0

Xeon Gold 6240 @ 2.60 GHz, Debian 9

min..max	MB/s	program	compiler or runtime
1.260..1.278s	266.8	freq03.cpp	gcc 6.3.0
1.492..1.521s	225.4	freq02.cpp	gcc 6.3.0
2.197..2.245s	153.0	freq01.rs	rustc 1.43.1
2.480..2.737s	135.5	freq01.cpp	gcc 6.3.0
3.880..4.187s	86.6	freq01.go	go 1.14.3
9.037..9.173s	37.2	freq01.php	php 7.4.6-nts
83.251..85.987s	4.0	freq01.py	python 3.5.3
1.349..1.442s	249.2	hack01.cpp	gcc 6.3.0

C++

g++ -O3 -o freq01 freq01.cpp
./freq01 pg.txt out.txt

Go

go build freq01.go
./freq01 pg.txt out.txt

Rust

cd build/rust
cargo build --release

cd ../..
./junk/freq01rust pg.txt out.txt

Scala

cd build/scala
sbt assembly
cd ../..
java -jar ./junk/freq01scala.jar pg.txt out.txt