The following expression was to be realized using 2-input AND and OR gates, but by mistake all 2-input AND gates were taken as 2-input NAND gates,
$$(a.b).c + (\bar a.c).d + (\bar b.c).d + a.d$$
What is the function finally realized ?
I have not indicated the k map properly but answer is 1
plz see this also:https://gateoverflow.in/3471/gate2007-it-38