Data commit

Task/Find-Chess960-starting-position-identifier/Go/find-chess960-starting-position-identifier.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+    "fmt"
+    "log"
+    "strings"
+)
+
+var glyphs = []rune("♜♞♝♛♚♖♘♗♕♔")
+var names = map[rune]string{'R': "rook", 'N': "knight", 'B': "bishop", 'Q': "queen", 'K': "king"}
+var g2lMap = map[rune]string{
+    '♜': "R", '♞': "N", '♝': "B", '♛': "Q", '♚': "K",
+    '♖': "R", '♘': "N", '♗': "B", '♕': "Q", '♔': "K",
+}
+
+var ntable = map[string]int{"01": 0, "02": 1, "03": 2, "04": 3, "12": 4, "13": 5, "14": 6, "23": 7, "24": 8, "34": 9}
+
+func g2l(pieces string) string {
+    lets := ""
+    for _, p := range pieces {
+        lets += g2lMap[p]
+    }
+    return lets
+}
+
+func spid(pieces string) int {
+    pieces = g2l(pieces) // convert glyphs to letters
+
+    /* check for errors */
+    if len(pieces) != 8 {
+        log.Fatal("There must be exactly 8 pieces.")
+    }
+    for _, one := range "KQ" {
+        count := 0
+        for _, p := range pieces {
+            if p == one {
+                count++
+            }
+        }
+        if count != 1 {
+            log.Fatalf("There must be one %s.", names[one])
+        }
+    }
+    for _, two := range "RNB" {
+        count := 0
+        for _, p := range pieces {
+            if p == two {
+                count++
+            }
+        }
+        if count != 2 {
+            log.Fatalf("There must be two %s.", names[two])
+        }
+    }
+    r1 := strings.Index(pieces, "R")
+    r2 := strings.Index(pieces[r1+1:], "R") + r1 + 1
+    k := strings.Index(pieces, "K")
+    if k < r1 || k > r2 {
+        log.Fatal("The king must be between the rooks.")
+    }
+    b1 := strings.Index(pieces, "B")
+    b2 := strings.Index(pieces[b1+1:], "B") + b1 + 1
+    if (b2-b1)%2 == 0 {
+        log.Fatal("The bishops must be on opposite color squares.")
+    }
+
+    /* compute SP_ID */
+    piecesN := strings.ReplaceAll(pieces, "Q", "")
+    piecesN = strings.ReplaceAll(piecesN, "B", "")
+    n1 := strings.Index(piecesN, "N")
+    n2 := strings.Index(piecesN[n1+1:], "N") + n1 + 1
+    np := fmt.Sprintf("%d%d", n1, n2)
+    N := ntable[np]
+
+    piecesQ := strings.ReplaceAll(pieces, "B", "")
+    Q := strings.Index(piecesQ, "Q")
+
+    D := strings.Index("0246", fmt.Sprintf("%d", b1))
+    L := strings.Index("1357", fmt.Sprintf("%d", b2))
+    if D == -1 {
+        D = strings.Index("0246", fmt.Sprintf("%d", b2))
+        L = strings.Index("1357", fmt.Sprintf("%d", b1))
+    }
+
+    return 96*N + 16*Q + 4*D + L
+}
+
+func main() {
+    for _, pieces := range []string{"♕♘♖♗♗♘♔♖", "♖♘♗♕♔♗♘♖", "♖♕♘♗♗♔♖♘", "♖♘♕♗♗♔♖♘"} {
+        fmt.Printf("%s or %s has SP-ID of %d\n", pieces, g2l(pieces), spid(pieces))
+    }
+}