View Compilation Error

231423_0_14199.cpp: In function `int main()':
231423_0_14199.cpp:6: error: conflicting declaration 'const float pi'
231423_0_14199.cpp:5: error: 'pi' has a previous declaration as `float pi'
231423_0_14199.cpp:6: error: declaration of `const float pi'
231423_0_14199.cpp:5: error: conflicts with previous declaration `float pi'
231423_0_14199.cpp:9: error: `setiosflags' undeclared (first use this function)
231423_0_14199.cpp:9: error: (Each undeclared identifier is reported only once for each function it appears in.)
231423_0_14199.cpp:9: error: `setprecision' undeclared (first use this function)