k-nucleotide Fortran gfortran program

! The Computer Language Benchmarks Game
! https://salsa.debian.org/benchmarksgame-team/benchmarksgame/

! There does not seem to be a Fortran library
! hash-table that could be used?
    

NOTES:
64-bit Ubuntu quad core
GNU Fortran (Ubuntu 9.2.1-9ubuntu2) 9.2.1 20191008


Wed, 06 May 2020 01:31:33 GMT

MAKE:
/usr/bin/gfortran -pipe -O3 -fomit-frame-pointer -march=core2  -fopenmp knucleotide.f95 -o knucleotide.gfortran_run 
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/Scrt1.o: in function `_start':
(.text+0x24): undefined reference to `main'
collect2: error: ld returned 1 exit status
make: [/home/dunham/8000-benchmarksgame/nanobench/makefiles/u64q.programs.Makefile:194: knucleotide.gfortran_run] Error 1 (ignored)
rm knucleotide.f95

3.43s to complete and log all make actions

COMMAND LINE:
./knucleotide.gfortran_run 0 < knucleotide-input250000.txt

MAKE ERROR