# make
gcc -g -o mutex_solution.out mutex_solution.c
# ./mutex_solution
/bin/sh: ./mutex_solution: not found
# ./mutex_solution.out
aantal = 30000000
# ./mutex_solution.out
aantal = 30000000
# time ./mutex_solution.out
aantal = 30000000
    3.38s real     2.92s user     0.05s system