def get_lower_resolution(elevation_map: List[List[int]]) -> List[List[int]]:
    '''Return a new elevation map, which is constructed from the values
    of elevation_map by decreasing the number of points within it.

    Precondition: elevation_map is a valid elevation map.

    >>> get_lower_resolution(
    ...     [[1, 6, 5, 6],
    ...      [2, 5, 6, 8],
    ...      [7, 2, 8, 1],
    ...      [4, 4, 7, 3]])
    [[3, 6], [4, 4]]
    >>> get_lower_resolution(
    ...     [[7, 9, 1],
    ...      [4, 2, 1],
    ...      [3, 2, 3]])
    [[5, 1], [2, 3]]
    '''
    newmap = []

    m = elevation_map
    for i in range(0, len(elevation_map)-1, 2):
        newmap.append([])
        for j in range(0, len(elevation_map[i]), 2):
            if len(elevation_map) % 2 == 0:
                s = m[i][j]
                s += m[i][j+1]
                s += +m[i+1][j]
                s += m[i+1][j+1]
                newmap[-1].append(int(s/4))
            else:

                s = elevation_map[i][j]
                s += elevation_map[i+1][j]
                newmap[-1].append(int(s/2))

                if in_matrix(elevation_map,[i,j+1]):







    return newmap