P<-matrix(c(0,1,0,0,0, 1,0,0,0,0, 1/2,0,0,1/2,0, 0,0,1/2,0,1/2, 0,1/2,0,1/2,0),ncol=5,byrow=T)
Q<-P[3:5,3:5]
M<-solve(diag(3)-Q)
x<-matrix(c(1,1,1),ncol=1)
M%*%x


P<-matrix(c(0,1,0,0,0, 1/2,0,1/2,0,0, 0,1/2,0,1/2,0, 0,0,1/2,0,1/2, 0,0,0,1,0),ncol=5,byrow=T)
Q<-P[-1,-1]
M<-solve(diag(4)-Q)
x<-matrix(c(1,1,1,1),ncol=1)
M%*%x


P<-matrix(c(0,1,0,0,0, 1,0,0,0,0, 1/2,0,0,1/2,0, 0,0,1/2,0,1/2, 0,1/2,0,1/2,0),ncol=5,byrow=T)
Q<-P[3:5,3:5]
S<-P[3:5,1:2]
M<-solve(diag(3)-Q)
M%*%S