写一个能够传递错误的子VI，子VI的功能是a+b=c，当有错误输入时，错误直接输出，c输出为0。当无错误输入时，进行正常计算。-Write a mistake to pass the sub-VI, sub-VI' s function is a+ b = c, when there is an error input, direct output error, c the output is 0. When the error-free input, the normal calculation.