program main
	implicit none
    character::s
    read(*,*)s
    if(s=='a')then
    	write(*,*)'b'
    else if(s=='b')
    	write(*,*) 'c'
    else if(s=='c')
    	write(*,*) 'd'
    else if(s=='e')
    	write(*,*) 'f'
    else if(s=='f')
    	write(*,*) 'g'
    else if(s=='g')
    	write(*,*) 'h'
    else if(s=='h')
    	write(*,*) 'i'
    else if(s=='i')
    	write(*,*) 'j'
    else if(s=='j')
    	write(*,*) 'k'
    else if(s=='k')
    	write(*,*) 'l'
    else if(s=='l')
    	write(*,*) 'm'
    else if(s=='m')
    	write(*,*) 'n'
    else if(s=='n')
    	write(*,*) 'o'
    else if(s=='o')
    	write(*,*) 'p'
    else if(s=='p')
    	write(*,*) 'q'
    else if(s=='q')
    	write(*,*) 'r'
    else if(s=='r')
    	write(*,*) 's'
    else if(s=='s')
    	write(*,*) 't'
    else if(s=='t')
    	write(*,*) 'u'
        
    else if(s=='u')
    	write(*,*) 'v'
    else if(s=='v')
    	write(*,*) 'w'
    else if(s=='w')
    	write(*,*) 'x'
    else if(s=='x')
    	write(*,*) 'y'
    else
    	write(*,*) 'z'
    end if
    stop
end program main