TRY ALL POSSIBLE BREAK - POINTS For any keystroke N , we need to loop from N - 3 keystrokes back to 1 keystroke to find a breakpoint ' b ' after which we will have Ctrl - A , Ctrl - C and then only Ctrl - V all the way .
$ b ; for ( $ b = $ N - 3 ; $ b >= 1 ; $ b -= 1 ) {