def fowardingunit(rs1,rs2,ex_mem_rd,mem_wb_rd,ex_mem_regwrite,mem_wb_regwrite):
    if rs1!=0 and rs1==ex_mem_rd and ex_mem_regwrite:
        forward_a='01'
    elif rs1!=0 and rs1==mem_wb_rd and mem_wb_regwrite:
        forward_a='10'
    else:
        forward_a='00'
    if rs2!=0 and rs2==ex_mem_rd and ex_mem_regwrite:
        forward_b='01'
    elif rs2!=0 and rs2==mem_wb_rd and mem_wb_regwrite:
        forward_b='10'
    else:
        forward_b='00'
    return forward_a,forward_b