4. 1億解までのピース変化
前節の実験で求めた1億解ですが、解のうち、1番目、100万番目、1千万番目、1億番目の4種の解を以下に示します。
ピースは左上から下にはめ込んでいき、解が完成すると右下から剥がしながら違うピースのはめ込みを試しています。このため、箱の左側はなかなか変化せず、右側だけが変化します。
【1番目の解】
+---+ | | +---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+ | | | | | | | | +---+---+ +---+ +---+ +---+---+ +---+ + +---+ +---+ + | | | | | | | | | | | | | + +---+ + +---+ +---+---+---+ +---+---+---+ + + +---+ + + | | | | | | | | | | | | | | + + +---+---+ +---+ +---+ +---+---+ +---+ + +---+---+---+ | | | | | | | | | | | | + +---+---+---+---+ +---+---+---+ + + +---+---+---+ + +---+ | | | | | | | | | | + +---+---+ +---+---+---+---+---+ + +---+---+---+ +---+---+ + + | | | | | | | | | | | +---+ +---+---+---+ + +---+---+---+---+---+---+---+---+---+ + | | | | | | | | +---+---+---+---+ +---+ +---+ +---+ +---+---+ +---+---+---+ +---+ | | | | | | | | | | | + +---+---+---+---+---+---+ +---+ +---+---+ +---+ +---+---+ + | | | | | | | | | | | +---+ +---+---+ +---+---+ +---+---+---+ +---+ + +---+ +---+ + | | | | | | | | | | | + +---+ +---+ +---+---+---+ +---+---+---+---+---+---+ + + | | | | | | | +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+【100万番目の解】
+---+ | | +---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+ | | | | | | | | +---+---+ +---+ +---+ +---+---+ +---+---+ + +---+---+ + | | | | | | | | | | | + +---+ + +---+ +---+---+---+ +---+ +---+ +---+---+---+---+ + | | | | | | | | | | | | | | + + +---+---+ +---+ +---+ +---+---+ + +---+---+---+ +---+---+ | | | | | | | | | | + +---+---+---+---+ +---+---+---+ + +---+---+---+---+ + +---+ + | | | | | | | | | | | | | + +---+---+ +---+---+---+---+---+ +---+ + + +---+ + + + | | | | | | | | | | | | | +---+ +---+---+---+ + +---+ + + +---+---+ + + | | | | | | | | | | +---+---+---+---+ +---+ +---+ +---+---+---+---+---+---+ +---+ + + | | | | | ★ | | | | | + +---+---+---+---+---+---+ +---+---+---+---+---+---+ +---+---+ + + | | | | | | | | | | +---+ +---+---+ +---+---+ +---+---+ + +---+ +---+ +---+---+ | | | | | | | | | | | | | + +---+ +---+ +---+---+---+ +---+ +---+ + +---+ +---+ + | | | | | | | | +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+動いたピースは右半分の★のピースまでの17個だけ。【1千万番目の解】
+---+ | | +---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+ | | | | | | | +---+---+ +---+ +---+ +---+---+---+ + +---+---+---+---+---+---+ | | | | | | | | | + +---+ + +---+ +---+---+---+ +---+---+ +---+---+---+ +---+ + | | | | | | | | | | | | | | | | + + +---+---+ +---+ +---+ + +---+---+ + +---+ + + | | | | | | | | | | | | | + +---+---+---+---+ +---+ +---+---+ +---+ + + + +---+ +---+ | | | | ★ | | | | | | | + +---+---+ +---+---+---+---+ +---+ + +---+ + +---+ +---+ + | | | | | | | | | | | | | +---+ +---+---+---+ +---+ +---+ +---+ +---+---+---+---+---+ | | | | | | | | | | +---+---+---+---+ +---+ +---+ +---+---+ + + +---+ +---+ + | | | | | | | | | | | | | + +---+---+---+---+---+---+ +---+---+---+ + +---+---+ +---+ + | | | | | | | | | +---+ +---+---+ +---+---+ +---+---+ + +---+---+ + +---+---+---+ | | | | | | | | | | | | + +---+ +---+ +---+---+---+ +---+ +---+ +---+---+ + + | | | | | | | | +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+★まで動いて、ようやく20個のピースが使われ始めた。【1億番目の解】
+---+ | | +---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+ | | | | | | | | +---+---+ +---+ +---+ +---+---+---+ + + +---+---+ + | | | | | | | | | | | + +---+ + +---+ +---+---+---+ +---+ + + +---+---+---+---+ | | | | | | | | | | | | | | + + +---+---+ +---+ +---+ +---+---+ +---+ + + + +---+ + | | | | | | | | | | | | | | | + +---+---+---+---+ +---+ +---+ +---+---+ +---+ + +---+ + + | | | | ★ | | | | | | | + +---+---+ +---+---+---+---+ +---+---+ + +---+---+ +---+ +---+ | | | | | | | | | | | | +---+ +---+---+---+ + +---+ + + + +---+---+---+ +---+ | | | | | | | | | | | | | +---+---+---+---+ +---+ +---+---+ + +---+ + +---+ +---+ + | | | | | | | | | | | + +---+---+---+---+---+---+ +---+ +---+ + +---+---+---+ +---+ + | | | | | | | | | | +---+ +---+---+ +---+---+ +---+---+ +---+---+ +---+---+---+ + | | | | | | | | | | | | + +---+ +---+ +---+---+---+ +---+---+ +---+---+ + +---+---+ | | | | | | | +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+動いたピースの位置は1千万番目と同じで、20個のピースしか動いていない。
ピースが増えるに従って急速に解が増えていくことが判る。1番目と1億番目を比較して動いていないピースを切り出すと以下のようになる。
+---+---+---+---+---+---+---+---+ | | | | +---+---+ +---+ +---+ +---+ | | | | | + +---+ + +---+ +---+---+---+ | | | | | | | | + + +---+---+ +---+ +---+ | | | | + +---+---+---+---+ +---+ | | | | + +---+---+ +---+---+---+---+ | | | | | +---+ +---+---+---+ + | | | | +---+---+---+---+ +---+ +---+ | | | | | + +---+---+---+---+---+---+ +---+ | | | | +---+ +---+---+ +---+---+ +---+---+ | | | | | | | + +---+ +---+ +---+---+---+ +---+ | | | | +---+---+---+---+---+---+---+---+---+-以上の結果は第2節で試した、100万回を求める場合の最小探索数になったピースのはめ込み順序で試したものです。このため、平均的なピースの動きになっていない可能性があります。また、100万解毎に結果を出力しているので、実際に幾つピースが動いたときにどの程度の解が求まっているのかはっきりしません。
そこでもっと定量的に、動いたピースと見つかった解の関係を求めてみることにしました。そこから全解を推定してみようというわけです。次節につづく。