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0_0_17960910_11580.cpp
0_0_17960910_11580.cpp(16) : error C2668: “log2”: 对重载函数的调用不明确
        VC2013\INCLUDE\math.h(1215): 可能是“long double log2(long double) throw()”
        VC2013\INCLUDE\math.h(1099): 或       “float log2(float) throw()”
        VC2013\INCLUDE\math.h(504): 或       “double log2(double)”
        尝试匹配参数列表“(int)”时
0_0_17960910_11580.cpp(17) : error C2668: “log2”: 对重载函数的调用不明确
        VC2013\INCLUDE\math.h(1215): 可能是“long double log2(long double) throw()”
        VC2013\INCLUDE\math.h(1099): 或       “float log2(float) throw()”
        VC2013\INCLUDE\math.h(504): 或       “double log2(double)”
        尝试匹配参数列表“(int)”时
0_0_17960910_11580.cpp(40) : error C2668: “log2”: 对重载函数的调用不明确
        VC2013\INCLUDE\math.h(1215): 可能是“long double log2(long double) throw()”
        VC2013\INCLUDE\math.h(1099): 或       “float log2(float) throw()”
        VC2013\INCLUDE\math.h(504): 或       “double log2(double)”
        尝试匹配参数列表“(int)”时
0_0_17960910_11580.cpp(41) : error C2668: “log2”: 对重载函数的调用不明确
        VC2013\INCLUDE\math.h(1215): 可能是“long double log2(long double) throw()”
        VC2013\INCLUDE\math.h(1099): 或       “float log2(float) throw()”
        VC2013\INCLUDE\math.h(504): 或       “double log2(double)”
        尝试匹配参数列表“(int)”时