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99 lines
1.6 KiB
99 lines
1.6 KiB
package day12
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import (
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"log"
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)
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type Waypoint struct {
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North, East int
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}
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type State2 struct {
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Waypoint Waypoint
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North, East int
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}
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func Solve2() {
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state := State2{
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Waypoint: Waypoint{North: 1, East: 10},
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North: 0,
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East: 0,
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}
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for _, row := range rows {
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switch row.Char {
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case "N":
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state.Waypoint.North += row.Arg
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case "S":
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state.Waypoint.North -= row.Arg
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case "E":
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state.Waypoint.East += row.Arg
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case "W":
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state.Waypoint.East -= row.Arg
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case "R":
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switch row.Arg % 360 {
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case 180:
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state.Waypoint.East *= -1
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state.Waypoint.North *= -1
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case 90:
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// Turn right a bit
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n := state.Waypoint.East * -1
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e := state.Waypoint.North
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state.Waypoint.North = n
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state.Waypoint.East = e
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case 270:
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// Turn left a bit
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n := state.Waypoint.East
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e := state.Waypoint.North * -1
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state.Waypoint.North = n
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state.Waypoint.East = e
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}
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case "L":
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switch row.Arg % 360 {
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case 180:
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state.Waypoint.East *= -1
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state.Waypoint.North *= -1
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case 90:
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// Turn right a bit
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n := state.Waypoint.East
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e := state.Waypoint.North * -1
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state.Waypoint.North = n
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state.Waypoint.East = e
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case 270:
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// Turn left a bit
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n := state.Waypoint.East * -1
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e := state.Waypoint.North
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state.Waypoint.North = n
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state.Waypoint.East = e
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}
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case "F":
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state.North += state.Waypoint.North * row.Arg
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state.East += state.Waypoint.East * row.Arg
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}
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}
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if state.East < 0 {
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state.East *= -1
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}
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if state.North < 0 {
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state.North *= -1
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}
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log.Printf("2020-12-12.02: Answer: %d\n", state.North+state.East)
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}
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