Java编写的24点纸牌游戏
任意4个1-13数字，加减乘除计算24点。
实现原理：
1）排列组合4个数字
2）计算每次排列组合的可能性
Cal24.java
importjava.util.HashSet;
importjava.util.Set;
publicclassCal24{
privatestaticfinaldoubleprecision=0.00001;
privatestaticfinalinttarget=24;
publicString[]execute(String[]inputs){
int[]digits=newint[4];
for(inti=0;i<inputs.length;i++){
digits[i]=Integer.valueOf(inputs[i]);
}
returnnewString[]{calc(digits)};
}
privateStringcalc(finalintdata[]){
finalSet<String>out=newHashSet<String>();
Combinationdigit=newCombination(){
@Override
protectedvoidhandle(int[]result){
finalint[]r=result;
Combinationoper=newCombination(){
@Override
protectedvoidhandle(int[]c){
doublex=r[0];
for(inti=0;i<r.length-1;i++){
x=doCalculate(x,r[i+1],c[i]);
}
if(Math.abs(Math.abs(x)-target)<precision||Math.abs(Math.abs(1/x)-target)<precision){
StringBuildersb=newStringBuilder();
for(intj=0;j<r.length;j++){
sb.append(r[j]);
if(j!=r.length-1){
sb.append(getOperation(c[j]));
}
}
out.add(sb.toString());
}
}
};
oper.combine(newint[]{0,1,2,3},data.length-1,true);
}
};
digit.combine(data);
StringBuildersb=newStringBuilder();
for(Stringstring:out){
sb.append(string);
sb.append("\n");
}
returnsb.toString();
}
privatedoubledoCalculate(doublex,doubley,intoperation){
switch(operation){
case0:
returnx+y;
case1:
returnx-y;
case2:
returnx*y;
case3:
returnx/y;
default:
return0;
}
}
privatestaticStringgetOperation(intoperation){
switch(operation){
case0:
return"+";
case1:
return"-";
case2:
return"*";
case3:
return"/";
default:
return"";
}
}
publicstaticvoidmain(String[]args){
System.out.println(newCal24().calc(newint[]{1,5,5,5}));
}
}
Combination.java
publicabstractclassCombination{
privatebooleanrepeat;
privateinttotal=0;
publicvoidcombine(intdata[]){
combine(data,data.length,false);
}
publicvoidcombine(intdata[],intcount){
combine(data,count,false);
}
publicvoidcombine(intdata[],intcount,booleanrepeat){
this.repeat=repeat;
inttimes=data.length;
intsize=(int)Math.pow(times,count);
for(inti=0;i<size;i++){
int[]result=toArray(data,i,count);
if(result!=null){
handle(result);
total++;
}
}
}
privateint[]toArray(intdata[],inti,intcount){
int[]indices=newint[count];
inttimes=data.length;
for(intj=0;j<count;j++){
inttemp=0;
if(i>0){
temp=i%times;
i=(i-temp)/times;
}
indices[j]=temp;
}
if(!repeat){
//removerepetition
for(intx=0;x<count;x++){
for(inty=0;y<count;y++){
if(x!=y){
if(indices[x]==indices[y])
returnnull;
}
}
}
}
int[]result=newint[count];
for(intx=0;x<count;x++){
intselected=data[indices[x]];
result[x]=selected;
}
returnresult;
}
publicintgetTotal(){
returntotal;
}
protectedabstractvoidhandle(int[]result);
}
以上所述就是本文的全部内容了，希望大家能够喜欢。