def pargen(left,right,ans): if(left==0 and right==0): print ans; if(left>0): pargen(left-1,right+1,ans+'('); if(right>0): pargen(left,right-1,ans+')'); pargen(3,0,''); #can pass any starting value as left,initial value of right is always 0.
def pargen(left,right,ans): if(left==0 and right==0): print ans; if(left>0): pargen(left-1,right+1,ans+'('); if(right>0): pargen(left,right-1,ans+')'); pargen(3,0,''); #can pass any starting value as left,initial value of right is always 0.