S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C
S =   (`_) -Y C