public static int MaxPath(PyramidDefinition pyramid)
{
for (int i = pyramid.Rows.Length - 1; i > 0; i--)
{
// for each row, take the highest from each pair and add to the row above
int[] row = pyramid.Rows[i];
int[] previousRow = pyramid.Rows[i-1];
for (int j = 0; j < row.Length-1; j++)
{
previousRow[j] += Math.Max(row[j], row[j+1]);
}
}
return pyramid.Rows[0][0];
}
public void PyramidMaxSumTests()
{
PyramidDefinition pyramid = new PyramidDefinition(new int[][]
{
new [] {55},
new [] {94, 48},
new [] {95, 30, 96},
new [] {77, 71, 26, 67},
});
Assert.AreEqual(321, PyramidMaxSumPath.MaxPath(pyramid));
PyramidDefinition pyramid2 = new PyramidDefinition(new int[][]
{
new [] {1},
new [] {1, 1},
new [] {1, 100, 1},
new [] {1, 1, 1, 1},
});
Assert.AreEqual(103, PyramidMaxSumPath.MaxPath(pyramid2));
}