day24: adding python z3, example

day24/hailMary.go

@@ -0,0 +1,73 @@
+package day24
+
+import (
+	"fmt"
+)
+
+// most inner loop
+// assumint stone hits h1 at t1, and h2 at t2
+// return the line. so 'HailParam' for my stone trajectory
+func AssumeHails(h1, h2 HailParam, t1, t2 int) (stoneTrajectory HailParam, isInt bool) {
+	Dx, isXInt := AssumedDelta(h1.p0.x, h2.p0.x, h1.Dx, h2.Dx, t1, t2)
+	Dy, isYInt := AssumedDelta(h1.p0.y, h2.p0.y, h1.Dy, h2.Dy, t1, t2)
+	Dz, isZInt := AssumedDelta(h1.p0.z, h2.p0.z, h1.Dz, h2.Dz, t1, t2)
+
+	isInt = isXInt && isYInt && isZInt
+
+	x := AssumedStartFromDelta(h1.p0.x, h1.Dx, t1, Dx)
+	y := AssumedStartFromDelta(h1.p0.y, h1.Dy, t1, Dy)
+	z := AssumedStartFromDelta(h1.p0.z, h1.Dz, t1, Dz)
+
+	stoneTrajectoryLine := fmt.Sprintf("%d, %d, %d @ %d, %d, %d", x, y, z, Dx, Dy, Dz)
+	stoneTrajectory = ReadHailLine(stoneTrajectoryLine)
+
+	return
+}
+
+func HailMaryLoop(hails []HailParam) {
+	// for t1, t2 from [1, 100]
+	// try to fit stoneTrajectory on every pair of hails.
+	// and hope for integer fit
+	for t1 := 1; t1 <= 100; t1++ {
+		for t2 := t1+1 ; t2 <= 100; t2++ {
+			for i, hail := range hails {
+			innerHail:
+				for j, otherHail := range hails {
+					if i == j {
+						continue innerHail
+					}
+					_, isInt := AssumeHails(hail, otherHail, t1, t2)
+					if !isInt {
+						continue innerHail // TODO first hope to loose
+					}
+					// if isInt {
+					// 	log.Printf("hail mary int fit between %s (%d) and %s (%d)",
+					// 		hail.SomeString(), t1,  otherHail.SomeString(), t2)
+					// }
+				}
+			}
+		}
+	}
+}
+
+// TODO check for inner loop : when get assumed stoneTrajectory
+// for all hail params, check that they intercept
+// func CheckAssumedTrajectory(assumedStone HailParam, hails []HailParam) bool {
+// 	for _, hail := range hails {
+// 		// i guess i could try to do what?
+// 		// assume oh, no. there can be t whatever
+// 	}
+// }
+
+func AssumedDelta(c1, c2 int, Dc1, Dc2 int, t1, t2 int) (delta int, isInt bool) {
+	divisor := t1 - t2
+	divisible := c1 - c2 + (t1 * Dc1) - (t2 * Dc2)
+
+	isInt = divisible % divisor == 0
+	delta = divisible / divisor
+	return
+}
+
+func AssumedStartFromDelta(c1 int, Dc1 int, t1, Dc int) (c int) {
+	return c1 + t1 * Dc1 - t1 * Dc
+}