View Compilation Error

0_0_15369793_29406.cpp
0_0_15369793_29406.cpp(7) : error C2057: 应输入常量表达式
0_0_15369793_29406.cpp(7) : error C2466: 不能分配常量大小为 0 的数组
0_0_15369793_29406.cpp(7) : error C2133: “a”: 未知的大小
0_0_15369793_29406.cpp(11) : error C2668: “pow”: 对重载函数的调用不明确
        VC2013\INCLUDE\math.h(1233): 可能是“long double pow(long double,int) throw()”
        VC2013\INCLUDE\math.h(1231): 或       “long double pow(long double,long double) throw()”
        VC2013\INCLUDE\math.h(1117): 或       “float pow(float,int) throw()”
        VC2013\INCLUDE\math.h(1115): 或       “float pow(float,float) throw()”
        VC2013\INCLUDE\math.h(1027): 或       “double pow(double,int) throw()”
        VC2013\INCLUDE\math.h(512): 或       “double pow(double,double)”
        尝试匹配参数列表“(int, int)”时