streams = [
    [1,2,2,4],
    [2,1,4,2],
    [3,4,1,3],
    [4,3,3,1]
    ]

placed = [
    [2,2,3],
    [2,3,2],
    [3,3,1]
    ]

# From Strimko Weekly Set 068
# See http://www.hakank.org/google_or_tools/strimko2.py
#
# Copyright 2010 Hakan Kjellerstrand hakank@bonetmail.com
#
# Licensed under the Apache License, Version 2.0 (the 'License'); 
# you may not use this file except in compliance with the License. 
# You may obtain a copy of the License at 
#
#     http://www.apache.org/licenses/LICENSE-2.0 
#
# Unless required by applicable law or agreed to in writing, software 
# distributed under the License is distributed on an 'AS IS' BASIS, 
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
# See the License for the specific language governing permissions and 
# limitations under the License.