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Graph Databases

Choose the route by travel time

BOTIE

Choose ROUTE relationships and calculate accumulated costs using minutes. Inspect the per-destination results before selecting the requested target.
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Context for this challenge

Choose ROUTE relationships and calculate accumulated costs using minutes. Inspect the per-destination results before selecting the requested target.

The fewest-hop shortcut loses to a longer route with lower accumulated minutes.

Inspect the component calculation
Calculate nonnegative path costs(
  Typed weighted relationships: Choose a relationship type(
    Relationships: Read graph relationships(
      Graph: Directed weighted route graph
    )
    Relationship type: ROUTE
  )
  Starting ID: Start location
  Cost field: minutes
)
Examples and results
Directed weighted route graph
The nodes and directed relationships in this value.Records: A; Location. B; Location. C; Location. D; Location. Relationships: A to B: ROUTE · minutes: 9. A to C: ROUTE · minutes: 2. C to B: ROUTE · minutes: 2. B to D: ROUTE · minutes: 1. C to D: ROUTE · minutes: 20. Full records and relationships are also listed below the diagram.A to B: ROUTE · minutes: 9ROUTE · minutes: 9ROUTE · minutes: 9A to C: ROUTE · minutes: 2ROUTE · minutes: 2ROUTE · minutes: 2C to B: ROUTE · minutes: 2ROUTE · minutes: 2ROUTE · minutes: 2B to D: ROUTE · minutes: 1ROUTE · minutes: 1ROUTE · minutes: 1C to D: ROUTE · minutes: 20ROUTE · minutes: 20ROUTE · minutes: 20AALocationLocationBBLocationLocationCCLocationLocationDDLocationLocation
Nodes and properties (4)
  • A · Location
  • B · Location
  • C · Location
  • D · Location
  • A to B: ROUTE · minutes: 9
  • A to C: ROUTE · minutes: 2
  • C to B: ROUTE · minutes: 2
  • B to D: ROUTE · minutes: 1
  • C to D: ROUTE · minutes: 20
Inspect the node and relationship records
{
  "nodes": [
    {
      "id": "A",
      "kind": "Location"
    },
    {
      "id": "B",
      "kind": "Location"
    },
    {
      "id": "C",
      "kind": "Location"
    },
    {
      "id": "D",
      "kind": "Location"
    }
  ],
  "edges": [
    {
      "id": "ab",
      "source": "A",
      "target": "B",
      "type": "ROUTE",
      "minutes": 9
    },
    {
      "id": "ac",
      "source": "A",
      "target": "C",
      "type": "ROUTE",
      "minutes": 2
    },
    {
      "id": "cb",
      "source": "C",
      "target": "B",
      "type": "ROUTE",
      "minutes": 2
    },
    {
      "id": "bd",
      "source": "B",
      "target": "D",
      "type": "ROUTE",
      "minutes": 1
    },
    {
      "id": "cd",
      "source": "C",
      "target": "D",
      "type": "ROUTE",
      "minutes": 20
    }
  ]
}
Start location
A
Required result
[
  {
    "id": "A",
    "cost": 0
  },
  {
    "id": "B",
    "cost": 4
  },
  {
    "id": "C",
    "cost": 2
  },
  {
    "id": "D",
    "cost": 5
  }
]
Directed weighted route graph
The nodes and directed relationships in this value.Records: A; Location. B; Location. C; Location. D; Location. Relationships: A to B: ROUTE · minutes: 9. A to C: ROUTE · minutes: 2. C to B: ROUTE · minutes: 2. B to D: ROUTE · minutes: 1. C to D: ROUTE · minutes: 20. Full records and relationships are also listed below the diagram.A to B: ROUTE · minutes: 9ROUTE · minutes: 9ROUTE · minutes: 9A to C: ROUTE · minutes: 2ROUTE · minutes: 2ROUTE · minutes: 2C to B: ROUTE · minutes: 2ROUTE · minutes: 2ROUTE · minutes: 2B to D: ROUTE · minutes: 1ROUTE · minutes: 1ROUTE · minutes: 1C to D: ROUTE · minutes: 20ROUTE · minutes: 20ROUTE · minutes: 20AALocationLocationBBLocationLocationCCLocationLocationDDLocationLocation
Nodes and properties (4)
  • A · Location
  • B · Location
  • C · Location
  • D · Location
  • A to B: ROUTE · minutes: 9
  • A to C: ROUTE · minutes: 2
  • C to B: ROUTE · minutes: 2
  • B to D: ROUTE · minutes: 1
  • C to D: ROUTE · minutes: 20
Inspect the node and relationship records
{
  "nodes": [
    {
      "id": "A",
      "kind": "Location"
    },
    {
      "id": "B",
      "kind": "Location"
    },
    {
      "id": "C",
      "kind": "Location"
    },
    {
      "id": "D",
      "kind": "Location"
    }
  ],
  "edges": [
    {
      "id": "ab",
      "source": "A",
      "target": "B",
      "type": "ROUTE",
      "minutes": 9
    },
    {
      "id": "ac",
      "source": "A",
      "target": "C",
      "type": "ROUTE",
      "minutes": 2
    },
    {
      "id": "cb",
      "source": "C",
      "target": "B",
      "type": "ROUTE",
      "minutes": 2
    },
    {
      "id": "bd",
      "source": "B",
      "target": "D",
      "type": "ROUTE",
      "minutes": 1
    },
    {
      "id": "cd",
      "source": "C",
      "target": "D",
      "type": "ROUTE",
      "minutes": 20
    }
  ]
}
Start location
A
Required result
[
  {
    "id": "A",
    "cost": 0
  },
  {
    "id": "B",
    "cost": 4
  },
  {
    "id": "C",
    "cost": 2
  },
  {
    "id": "D",
    "cost": 5
  }
]
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Assumptions and test precision

These components operate on the supplied records in your browser. They do not run a graph database or interpret Cypher. Numerical tests allow a difference of 0.001. Lists and structures must also have the right shape.

Your last tested pieces can start the full construction. An existing draft there keeps its own pieces.

A zero-cost transfer returns to the starting point

This check uses the pieces from “Read the destination without inventing reachability”.

BOTIE

The direct R-to-T route takes eight minutes. R-to-A and A-to-R take zero, A-to-B takes two, and B-to-T takes one. A zero-cost NEAR edge also connects R to T. Predict the least travel time using ROUTE edges only.
Directed weighted route graph
The nodes and directed relationships in this value.Records: R; Location. A; Location. B; Location. T; Location. Relationships: R to T: ROUTE · minutes: 8. R to A: ROUTE · minutes: 0. A to R: ROUTE · minutes: 0. A to B: ROUTE · minutes: 2. B to T: ROUTE · minutes: 1. R to T: NEAR · minutes: 0. Full records and relationships are also listed below the diagram.R to T: ROUTE · minutes: 8ROUTE · minutes: 8ROUTE · minutes: 8R to A: ROUTE · minutes: 0ROUTE · minutes: 0ROUTE · minutes: 0A to R: ROUTE · minutes: 0ROUTE · minutes: 0ROUTE · minutes: 0A to B: ROUTE · minutes: 2ROUTE · minutes: 2ROUTE · minutes: 2B to T: ROUTE · minutes: 1ROUTE · minutes: 1ROUTE · minutes: 1R to T: NEAR · minutes: 0NEAR · minutes: 0NEAR · minutes: 0RRLocationLocationAALocationLocationBBLocationLocationTTLocationLocation
Nodes and properties (4)
  • R · Location
  • A · Location
  • B · Location
  • T · Location
  • R to T: ROUTE · minutes: 8
  • R to A: ROUTE · minutes: 0
  • A to R: ROUTE · minutes: 0
  • A to B: ROUTE · minutes: 2
  • B to T: ROUTE · minutes: 1
  • R to T: NEAR · minutes: 0
Inspect the node and relationship records
{
  "nodes": [
    {
      "id": "R",
      "kind": "Location"
    },
    {
      "id": "A",
      "kind": "Location"
    },
    {
      "id": "B",
      "kind": "Location"
    },
    {
      "id": "T",
      "kind": "Location"
    }
  ],
  "edges": [
    {
      "id": "direct",
      "source": "R",
      "target": "T",
      "type": "ROUTE",
      "minutes": 8
    },
    {
      "id": "transfer",
      "source": "R",
      "target": "A",
      "type": "ROUTE",
      "minutes": 0
    },
    {
      "id": "back",
      "source": "A",
      "target": "R",
      "type": "ROUTE",
      "minutes": 0
    },
    {
      "id": "ab",
      "source": "A",
      "target": "B",
      "type": "ROUTE",
      "minutes": 2
    },
    {
      "id": "bt",
      "source": "B",
      "target": "T",
      "type": "ROUTE",
      "minutes": 1
    },
    {
      "id": "near",
      "source": "R",
      "target": "T",
      "type": "NEAR",
      "minutes": 0
    }
  ]
}
Start location
R
Destination
T

Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.

Build a construction in the workspace above first. This case will test those pieces.

Why can the stale nine-minute B entry be skipped after a four-minute route has been recorded?

Separate the best known value from old queued candidates, and state the weight assumptions that justify settlement.

These components operate on the supplied records in your browser. They do not run a graph database or interpret Cypher.

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