We will have 4 states
P,Q,R,S
all a will be taken by P (PUSH THEM INTO STACK)...on first occurance of b we will go to Q(PUSH ALL B INTO STACK) accept all b ...on first occurance of c goto R
now for each c pop a OR b ....so if we have empty stack on episolon , then goto new state S which is final state.
There must be one more trasition from P to S that is on elisolon and empty stack M=0 and N=0 will be accpted .