open System

let n  = Console.ReadLine()
let n1 : int = int n
let mutable a = Array2D.init n1 n1 (fun i j -> Console.Read())

for k = 1 to n1 - 1 do
    for j = k to n1 - 1 do
        m <- a.[j, k - 1] / a.[k - 1, k - 1]
        for i = 0 to n1 - 1 do
            a.[j, i] <- a.[j, i] - m * a.[k - 1, i]