Data commit

Task/Generate-Chess960-starting-position/Go/generate-chess960-starting-position.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+    "fmt"
+    "math/rand"
+)
+
+type symbols struct{ k, q, r, b, n rune }
+
+var A = symbols{'K', 'Q', 'R', 'B', 'N'}
+var W = symbols{'♔', '♕', '♖', '♗', '♘'}
+var B = symbols{'♚', '♛', '♜', '♝', '♞'}
+
+var krn = []string{
+    "nnrkr", "nrnkr", "nrknr", "nrkrn",
+    "rnnkr", "rnknr", "rnkrn",
+    "rknnr", "rknrn",
+    "rkrnn"}
+
+func (sym symbols) chess960(id int) string {
+    var pos [8]rune
+    q, r := id/4, id%4
+    pos[r*2+1] = sym.b
+    q, r = q/4, q%4
+    pos[r*2] = sym.b
+    q, r = q/6, q%6
+    for i := 0; ; i++ {
+        if pos[i] != 0 {
+            continue
+        }
+        if r == 0 {
+            pos[i] = sym.q
+            break
+        }
+        r--
+    }
+    i := 0
+    for _, f := range krn[q] {
+        for pos[i] != 0 {
+            i++
+        }
+        switch f {
+        case 'k':
+            pos[i] = sym.k
+        case 'r':
+            pos[i] = sym.r
+        case 'n':
+            pos[i] = sym.n
+        }
+    }
+    return string(pos[:])
+}
+
+func main() {
+    fmt.Println(" ID  Start position")
+    for _, id := range []int{0, 518, 959} {
+        fmt.Printf("%3d  %s\n", id, A.chess960(id))
+    }
+    fmt.Println("\nRandom")
+    for i := 0; i < 5; i++ {
+        fmt.Println(W.chess960(rand.Intn(960)))
+    }
+}