Mario starts task 0
Ariel starts task 1
Piera starts task 2
Carlo starts task 3
Luigi starts task 0                       //two tasks #0 in parallel!!!
                    Carlo ends task 3
                    Ariel ends task 1
Ariel starts task 1
Beppe starts task 2                       //two tasks #2 in parallel!!!
                    Luigi ends task 0
Carlo starts task 3
                    Mario ends task 0                    
Mario starts task 0
                    Ariel ends task 1
                    Piera ends task 2
Ariel starts task 1
                    Beppe ends task 2
Piera starts task 2
                    Piera ends task 2
                    Mario ends task 0
                    Ariel ends task 1
                    Carlo ends task 3
^C
alonzo:~/www/assignments
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