How many times does line $10$ execute?

for $i$ in $1..$N loop

for $j$ in $1..$i loop

for $k$ in $i..j$ loop

Sum :$=$ Sum $+1$;

end loop;

end loop;

end loop;

for $p$ in $1..$N$*$N loop

for $q$ in $1..$p loop

Sum :$=$ Sum $-1$;

end loop;

end loop;