Init

Makefile

@@ -0,0 +1,30 @@
+SRC = $(wildcard *.dot)
+FMT = jpg
+OBJ = ${SRC:.dot=.${FMT}}
+VID = search.mp4
+
+all: search recurse movie
+
+clean:
+	rm -f *.${FMT}
+	rm -f step*.dot
+	rm -f ${VID}
+
+graphs: ${OBJ}
+
+recurse:
+	@echo "Generating .${FMT}s..."
+	@$(MAKE) graphs
+	@echo "...done."
+
+search:
+	@echo "Searching path..."
+	@go run hamilton.go || echo "Found nothing."
+
+movie:
+	@ffmpeg -y -f image2 -r 2/1 -i step%07d.jpg -c:v libx264 -s "1920x1080" ${VID}
+
+%.${FMT}: %.dot
+	@neato $< -T${FMT} -o $@
+
+.PHONY: all clean search graphs recurse movie

Readme

@@ -0,0 +1,8 @@
+Beispielcode für das Rätsel in Rezos Video ( https://youtu.be/MVajSA0Itq4?t=240 )
+
+Was ihr braucht, um das Programm auszuführen und das Rätsel zu durchlaufen:
+
+- make
+- Go
+- Graphviz
+- ffmpeg

grid0.dot

@@ -0,0 +1,26 @@
+graph grid
+{
+	dpi=300; 
+	layout=dot
+	labelloc = "c"
+	node [label="",shape=circle, style=filled, color=chartreuse4]
+	// arbitrary path on rigid grid
+	edge [weight=1000 color=dimgrey minlen=2.0 len=2.0]
+
+	// uncomment to hide the grid
+	edge [style=invis]
+
+	A0 -- A1 -- A2 -- A3 -- A4 
+	B0 -- B1 -- B2 -- B3 -- B4 
+	C0 -- C1 -- C2 -- C3 -- C4 
+	D0 -- D1 -- D2 -- D3 -- D4 
+	E0 -- E1 -- E2 -- E3 -- E4 
+	
+	rank=same {A0 -- B0 -- C0 -- D0 -- E0}
+	rank=same {A1 -- B1 -- C1 -- D1 -- E1}
+	rank=same {A2 -- B2 -- C2 -- D2 -- E2}
+	rank=same {A3 -- B3 -- C3 -- D3 -- E3}
+	rank=same {A4 -- B4 -- C4 -- D4 -- E4}
+
+        A0,A1,B0,B1,C1,D1,D2 [color=crimson]
+}

grid1.dot

@@ -0,0 +1,26 @@
+graph grid
+{
+	dpi=300; 
+	layout=dot
+	labelloc = "c"
+	node [label="",shape=circle, style=filled, color=chartreuse4]
+	// arbitrary path on rigid grid
+	edge [weight=1000 color=dimgrey minlen=2.0 len=2.0]
+
+	// uncomment to hide the grid
+	//edge [style=invis]
+
+	A0 -- A1 -- A2 -- A3 -- A4 
+	B0 -- B1 -- B2 -- B3 -- B4 
+	C0 -- C1 -- C2 -- C3 -- C4 
+	D0 -- D1 -- D2 -- D3 -- D4 
+	E0 -- E1 -- E2 -- E3 -- E4 
+	
+	rank=same {A0 -- B0 -- C0 -- D0 -- E0}
+	rank=same {A1 -- B1 -- C1 -- D1 -- E1}
+	rank=same {A2 -- B2 -- C2 -- D2 -- E2}
+	rank=same {A3 -- B3 -- C3 -- D3 -- E3}
+	rank=same {A4 -- B4 -- C4 -- D4 -- E4}
+
+        A0,A1,B0,B1,C1,D1,D2 [color=crimson]
+}

grid2.dot

@@ -0,0 +1,26 @@
+graph grid
+{
+	dpi=300; 
+	layout=dot
+	labelloc = "c"
+	node [label="",shape=circle, style=filled, color=chartreuse4]
+	// arbitrary path on rigid grid
+	edge [weight=1000 color=dimgrey minlen=2.0 len=2.0]
+
+	// uncomment to hide the grid
+	//edge [style=invis]
+
+	            A2 -- A3 -- A4 
+	            B2 -- B3 -- B4 
+	            C2 -- C3 -- C4 
+	                  D3 -- D4 
+	E0 -- E1 -- E2 -- E3 -- E4 
+	
+	rank=same {C0 -- D0 -- E0}
+	rank=same {E1}
+	rank=same {A2 -- B2 -- C2}
+	rank=same {A3 -- B3 -- C3 -- D3 -- E3}
+	rank=same {A4 -- B4 -- C4 -- D4 -- E4}
+
+        //A0,A1,B0,B1,C1,D1,D2 [color=crimson]
+}

grid3.dot

@@ -0,0 +1,43 @@
+graph grid
+{
+	dpi=300; 
+	layout=dot
+	labelloc = "c"
+	node [label="",shape=circle, style=filled, color=chartreuse4]
+	// arbitrary path on rigid grid
+	edge [weight=1000 color=dimgrey minlen=2.0 len=2.0]
+
+	// uncomment to hide the grid
+	//edge [style=invis]
+
+	            A2 -- A3 -- A4 
+	            B2 -- B3 -- B4 
+	            C2 -- C3 -- C4 
+	                  D3 -- D4 
+	E0 -- E1 -- E2 -- E3 -- E4 
+	
+	rank=same {C0 -- D0 -- E0}
+	rank=same {E1}
+	rank=same {A2 -- B2 -- C2}
+	rank=same {A3 -- B3 -- C3 -- D3 -- E3}
+	rank=same {A4 -- B4 -- C4 -- D4 -- E4}
+
+	C0 [xlabel="0"]
+	D0 [xlabel="1"]
+	E0 [xlabel="2"]
+	E1 [xlabel="3"]
+	E2 [xlabel="4"]
+	E3 [xlabel="5"]
+	E4 [xlabel="6"]
+	D4 [xlabel="7"]
+	C4 [xlabel="8"]
+	B4 [xlabel="9"]
+	A4 [xlabel="10"]
+	A3 [xlabel="11"]
+	B3 [xlabel="12"]
+	C3 [xlabel="13"]
+	D3 [xlabel="14"]
+	A2 [xlabel="15"]
+	B2 [xlabel="16"]
+	C2 [xlabel="17"]
+}

grid4.dot

@@ -0,0 +1,50 @@
+digraph {
+dpi=200
+node [shape=circle, style=filled]
+0  ->  1
+1  ->  0
+1  ->  2
+2  ->  1
+2  ->  3
+3  ->  2
+3  ->  4
+4  ->  3
+4  ->  5
+5  ->  4
+5  ->  6
+5  ->  14
+6  ->  5
+6  ->  7
+7  ->  6
+7  ->  8
+7  ->  14
+8  ->  7
+8  ->  9
+8  ->  13
+9  ->  8
+9  ->  10
+9  ->  12
+10  ->  9
+10  ->  11
+11  ->  10
+11  ->  12
+11  ->  15
+12  ->  9
+12  ->  11
+12  ->  13
+12  ->  16
+13  ->  8
+13  ->  12
+13  ->  14
+13  ->  17
+14  ->  5
+14  ->  7
+14  ->  13
+15  ->  11
+15  ->  16
+16  ->  12
+16  ->  15
+16  ->  17
+17  ->  13
+17  ->  16
+}

hamilton.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"fmt"
+	"os"
+)
+
+var g [][]int = [][]int{
+	[]int{1},
+	[]int{0, 2},
+	[]int{1, 3},
+	[]int{2, 4},
+	[]int{3, 5},
+	[]int{4, 6, 14},
+	[]int{5, 7},
+	[]int{6, 8, 14},
+	[]int{7, 9, 13},
+	[]int{8, 10, 12},
+	[]int{9, 11},
+	[]int{10, 12, 15},
+	[]int{9, 11, 13, 16},
+	[]int{8, 12, 14, 17},
+	[]int{5, 7, 13},
+	[]int{11, 16},
+	[]int{12, 15, 17},
+	[]int{13, 16},
+}
+
+var step int
+
+func writeGraphfile(g [][]int, path []int) {
+	filename := fmt.Sprintf("step%07d.dot", step)
+	f, _ := os.Create(filename)
+	step++
+	fmt.Fprintln(f, "digraph {")
+	fmt.Fprintln(f, "dpi=200")
+	fmt.Fprintln(f, "node [shape=circle, style=filled, label=\"\"]")
+	for v1, adjlist := range g {
+		for _, v2 := range adjlist {
+			fmt.Fprintln(f, v1, " -> ", v2)
+		}
+	}
+	for i, _ := range g {
+		fmt.Fprintln(f, i, "[xlabel=x]")
+	}
+	for i, v := range path {
+		fmt.Fprintln(f, v, "[xlabel=", i, "]")
+		fillcolor := "red"
+		if i == 0 {
+			fillcolor = "blue"
+		} else if i == len(path)-1 {
+			fillcolor = "yellow"
+		}
+		fmt.Fprintln(f, v, "[fillcolor=", fillcolor, "]")
+	}
+	fmt.Fprintln(f, "}")
+}
+
+func contains(path []int, v int) bool {
+	for _, w := range path {
+		if w == v {
+			return true
+		}
+	}
+	return false
+}
+
+func DFS(g [][]int, path []int) {
+	deadend := true
+	for _, v2 := range g[path[len(path)-1]] {
+		if contains(path, v2) {
+			continue
+		}
+		deadend = false
+		path2 := append(path, v2)
+		DFS(g, path2)
+	}
+	if len(path) == len(g) {
+		fmt.Println("Found path: ", path)
+		writeGraphfile(g, path)
+		os.Exit(0)
+	} else if deadend {
+		writeGraphfile(g, path)
+	}
+}
+
+func main() {
+	step = 0
+	writeGraphfile(g, []int{})
+	DFS(g, []int{0})
+	os.Exit(-1)
+}