Hi Usman,
Using the statement if ((led1==1 || led2 && led3 == 0)==1) you are trying to read port bits 0,1 and 2 of port A which are already set as output. It is always better to avoid reading an output port.
Again you should always careful about using proper brackets like;
if ( ( ( led1==1 ) || ( ( led2 && led3 ) == 0 ) ) ==1 )