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;LIBHDR ACK(M,N) M==0?N+1,N==0?ACK(M-1,1),ACK(M-1,ACK(M,N-1)) MAIN(;N,M) [ N=0; N<=6 @ [ M=0; M<=3 @ [ WRITEF("ACK(%N,%N) = %N*N",M,N,ACK(M,N)); ++M ]; ++N ] ]