編譯錯誤， 請檢查語法是否符合系統『ANSI/ISO C/C++ by GNU』的要求。
錯誤訊息：
/tmp/code_42342.cpp: In function `int main(int, char**)':
/tmp/code_42342.cpp:15: error: call of overloaded `sqrt(int&)' is ambiguous
/usr/include/bits/mathcalls.h:157: error: candidates are: double sqrt(double)
/usr/include/c++/3.3/cmath:550: error: long double
std::sqrt(long double)
/usr/include/c++/3.3/cmath:546: error: float std::sqrt(float)
/tmp/code_42342.cpp:23: error: call of overloaded `sqrt(int&)' is ambiguous
/usr/include/bits/mathcalls.h:157: error: candidates are: double sqrt(double)
/usr/include/c++/3.3/cmath:550: error: long double
std::sqrt(long double)
/usr/include/c++/3.3/cmath:546: error: float std::sqrt(float)