error C2668: 'sqrt' : ambiguous call to overloaded function
分析：模棱两可的函数调用，（在oj上提交会编译出错）Compile ErrorMain.cppF:\temp\19889863.2398\Main.cpp(21) : error C2668: 'sqrt' : ambiguous call to overloaded function math.h(581): could be 'long double sqr...
