Data commit

Task/Dice-game-probabilities/Sidef/dice-game-probabilities.sidef

@@ -0,0 +1,30 @@
+func combos(sides, n) {
+    n || return [1]
+    var ret = ([0] * (n*sides.max + 1))
+    combos(sides, n-1).each_kv { |i,v|
+        v && for s in sides { ret[i + s] += v }
+    }
+    return ret
+}
+
+func winning(sides1, n1, sides2, n2) {
+    var (p1, p2) = (combos(sides1, n1), combos(sides2, n2))
+    var (win,loss,tie) = (0,0,0)
+    p1.each_kv { |i, x|
+        win  += x*p2.ft(0,i-1).sum
+        tie  += x*p2.ft(i, i).sum
+        loss += x*p2.ft(i+1).sum
+    }
+    [win, tie, loss] »/» p1.sum*p2.sum
+}
+
+func display_results(String title, Array res) {
+    say "=> #{title}"
+    for name, prob in (%w(p₁\ win tie p₂\ win) ~Z res) {
+        say "P(#{'%6s' % name}) =~ #{prob.round(-11)} (#{prob.as_frac})"
+    }
+    print "\n"
+}
+
+display_results('9D4 vs 6D6',  winning(range(1, 4), 9, range(1,6), 6))
+display_results('5D10 vs 6D7', winning(range(1,10), 5, range(1,7), 6))