'Find the smallest uncovered value in the matrix.'

def __find_smallest(self):

    minval = sys.maxsize
    for i in range(self.n):
        for j in range(self.n):
            if ((not self.row_covered[i]) and (not self.col_covered[j])):
                if (minval > self.C[i][j]):
                    minval = self.C[i][j]
    return minval
