sisoku

sisoku.py

#coding:utf-8
from __future__ import division  #整数割り算時の切り捨て解除
#演算子と文字列（出力用）のリスト
funcs=[lambda x,y:x+y,lambda x,y:x-y,lambda x,y:y-x,lambda x,y:x*y,lambda x,y:x/y,lambda x,y:y/x] 
sikifuncs=[lambda x,y:"("+x+"+"+y+")",lambda x,y:"("+x+"-"+y+")",lambda x,y:"("+y+"-"+x+")",lambda x,y:"("+x+"*"+y+")",lambda x,y:"("+x+"/"+y+")",lambda x,y:"("+y+"/"+x+")"]


def make(numlist,ans,siki):
	L=len(numlist)
	if L==1: 
		if abs(numlist[0]-ans)<1/100000.0: 
			return siki
	        else:return False
	
	else:
		for i in range(6):
			for j in range(L-1):                
				n=numlist[:]
				s=siki[:]
				try:
					n.insert(j,funcs[i](n.pop(j),n.pop(j)))
					s.insert(j,sikifuncs[i](s.pop(j),s.pop(j)))
				except ZeroDivisionError:
					continue
				res=make(n,ans,s)	
				if res: return res
		return False

#並び替え関数
def conb(numlist,x):
	if x==0: return [[]]
	else: return [[a]+b for i,a in enumerate(numlist) for b in conb(numlist[:i]+numlist[i+1:],x-1)]
		
#重複
def setlist(list):
	res=[]
	while len(list):
		if not res.count(list[0]):res.append(list.pop(0))
		list.pop(0)
	return res

def solve(numlist,ans):
	numlists=conb(numlist,len(numlist))
	numlists=setlist(numlists)
	for list in numlists:
		siki=map(str,list)
		res=make(list,ans,siki)
		if res:yield res[0]
	yield False