If we have LUP,we can solve the equations in O(n2) LUP-SOLVE(L,U,π，b) 1 n L.rows 2 let x be a new vector of length n 3 fori 1ton 4 y=b0-∑1y 5 for i =n downto l 6 x=(y-∑=i+14)/a 7 return x But,how can we get LUP?If we have LUP, we can solve the equations in Θ(n2 ) But, how can we get LUP?