/in/foo.cc: In function 'int main()':
/in/foo.cc:5:14: warning: variable 'm' set but not used [-Wunused-but-set-variable]
 double a[10],m,n,temp;
              ^
/in/foo.cc:5:16: warning: variable 'n' set but not used [-Wunused-but-set-variable]
 double a[10],m,n,temp;
                ^