fortran中的编译错误:名称中的无效字符(1)

I have written a code in FORTRAN for conjugate gradient method... There is an error and i am not able to solve it after hours of working on it! The attached code is a subroutine to do the CGR and it is part of my main program which consists of 2 functions and other subroutines.I have written a code in FORTRAN for conjugate