def main():
with open(sys.argv[1]) as f:
lines = f.read().splitlines()
adj = []
for line in lines:
row = []
for node in line.split(','):
if node == '-':
row.append(None)
else:
row.append(int(node))
adj.append(row)
num_nodes = len(adj)
# make sure the adjacency matrix is square
assert all(len(row) == num_nodes for row in adj)
graph = WeightedGraph()
for i in range(num_nodes):
graph.add_node(i)
for x, row in enumerate(adj):
for y, weight in enumerate(row):
if weight is not None:
graph.add_arc(x, y, weight)
mst = min_spanning_tree(graph)
# Now we want to consider half of the adjacency matrix, so we can
# sum the total weight of all arcs.
half_adj = []
for i, row in enumerate(adj):
new_row = []
for j, weight in enumerate(row):
if i <= j:
new_row.append(weight)
else:
new_row.append(None)
half_adj.append(new_row)
# Now remove all of the arcs in the mst, so the arcs we are left
# with are the ones that we are able to remove.
for mst_arc_source, mst_arc_target in mst:
half_adj[mst_arc_source][mst_arc_target] = None
half_adj[mst_arc_target][mst_arc_source] = None
print(sum(sum(filter(None, row)) for row in half_adj))
def main():
global matrix
with open(sys.argv[1]) as f:
lines = f.readlines()
matrix = [[int(n) for n in l.strip().split(',')] for l in lines]
"""
matrix = [[131, 673, 234, 103, 18],
[201, 96, 342, 965, 150],
[630, 803, 746, 422, 111],
[537, 699, 497, 121, 956],
[805, 732, 524, 37, 331]]
"""
matrix_size = len(matrix)
# the cost of arriving at each node is the value at that node
g = WeightedGraph()
for lnum, line in enumerate(matrix):
for cnum, value in enumerate(line):
g.add_node((lnum, cnum))
# from below
if (0 <= lnum + 1 < matrix_size):
g.add_arc((lnum + 1, cnum), (lnum, cnum), value)
# from above
if (0 <= lnum - 1 < matrix_size):
g.add_arc((lnum - 1, cnum), (lnum, cnum), value)
# from right
if (0 <= cnum + 1 < matrix_size):
g.add_arc((lnum, cnum + 1), (lnum, cnum), value)
# from left
if (0 <= cnum - 1 < matrix_size):
g.add_arc((lnum, cnum - 1), (lnum, cnum), value)
route, cost = a_star(g, (0, 0), (matrix_size - 1, matrix_size - 1))
print(cost + matrix[0][0])
