我正在尝试用java创建24游戏来练习。 24 Game是一种算术游戏，其目标是找到一种操纵四个整数的方法，使得最终结果为24.可以使用任何数字顺序的加法，减法，乘法或除法来制作四位数操作从一到九等于24.
规则很简单：你只需要使用每个数字一次，只使用从用户那里读取的4个数字来找到一个方程式来获得24。
基本上我的问题是我试图将等式== 24附加到StringBuffer输出。我可能错误地使用StringBuffer。我想将所有方程式添加到StringBuffer中，然后在将StringBuffer打印到控制台之前删除所有重复的方程式。然而，无论所有方程打印什么，我都不确定为什么。我不确定StringBuffer是否可以实现这一点，因为它可能只附加字符。
int i = 0;
public void Solve(double w, double x, double y, double z){
double [] nums = {w,x,y,z};
int length = nums.length;
double eHold=0, fHold=0;
boolean [] used = new boolean[length];
StringBuffer output = new StringBuffer(400);
int position = 0;
int value = 0;
if (position == nums.length){
//for (int i=0; i<output.length();i++){
//if (output.)
System.out.println("");
return;
//}
}
else {
for (int i=0; i<nums.length; i++){
if (((nums[i]/nums[i+1])*fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" * ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else if (((nums[i]/nums[i+1])-fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" - ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])-fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" - ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])/fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" / ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else if (((nums[i]-nums[i+1])*fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" * ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else if (((nums[i]-nums[i+1])/fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" / ("+nums[i+3]+" + "+nums[i+4]+")" + " = 24");
else value++;
fHold=nums[i+3]-nums[i+4];
if (((nums[i]/nums[i+1])*fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" * ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else if (((nums[i]/nums[i+1])+fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" + ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])+fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" + ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])/fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" / ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])*fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" * ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])/fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" / ("+nums[i+3]+" - "+nums[i+4]+")" + " = 24");
else value++;
fHold=nums[i+3]*nums[i+4];
if (((nums[i]/nums[i+1])-fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" * ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else if (((nums[i]/nums[i+1])+fHold)==24)
output.append (nums[i]+" / "+nums[i+1]+" + ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else if (((nums[i]-nums[i+1])+fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" + ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else if (((nums[i]-nums[i+1])/fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" / ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])-fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" - ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])/fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" / ("+nums[i+3]+" * "+nums[i+4]+")" + " = 24");
else value++;
fHold=nums[i+3]/nums[i+4];
if (((nums[i]-nums[i+1])*fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" * ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else if (((nums[i]-nums[i+1])+fHold)==24)
output.append (nums[i]+" - "+nums[i+1]+" + ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])+fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" + ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else if (((nums[i]*nums[i+1])-fHold)==24)
output.append (nums[i]+" * "+nums[i+1]+" - ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])*fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" * ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else if (((nums[i]+nums[i+1])-fHold)==24)
output.append (nums[i]+" + "+nums[i+1]+" - ("+nums[i+3]+" / "+nums[i+4]+")" + " = 24");
else value++;
fHold=nums[i+1]*nums[i+3];
if (((nums[i]-fHold)/nums[i+4])==24)
output.append (nums[i]+" - ("+nums[i+1]+" * "+nums[i+3]+") / "+nums[i+4] + " = 24");
else if (((nums[i]-fHold)+nums[i+4])==24)
output.append (nums[i]+" - ("+nums[i+1]+" * "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)+nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" * "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)-nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" * "+nums[i+3]+") - "+nums[i+4] + " = 24");
else if (((nums[i]+fHold)/nums[i+4])==24)
output.append (nums[i]+" + ("+nums[i+1]+" * "+nums[i+3]+") / "+nums[i+4] + " = 24");
else if (((nums[i]+fHold)-nums[i+4])==24)
output.append (nums[i]+" + ("+nums[i+1]+" * "+nums[i+3]+") - "+nums[i+4] + " = 24");
else value++;
fHold=nums[i+1]-nums[i+3];
if (((nums[i]*fHold)/nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" - "+nums[i+3]+") / "+nums[i+4] + " = 24");
else if (((nums[i]*fHold)+nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" - "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)+nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" - "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)*nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" - "+nums[i+3]+") * "+nums[i+4] + " = 24");
else value++;
fHold=nums[i+1]/nums[i+3];
if (((nums[i]-fHold)*nums[i+4])==24)
output.append (nums[i]+" - ("+nums[i+1]+" / "+nums[i+3]+") * "+nums[i+4] + " = 24");
else if (((nums[i]-fHold)+nums[i+4])==24)
output.append (nums[i]+" - ("+nums[i+1]+" / "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]*fHold)+nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" / "+nums[i+3]+") + "+nums[i+4] + " = 24");
else if (((nums[i]*fHold)-nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" / "+nums[i+3]+") - "+nums[i+4] + " = 24");
else if (((nums[i]+fHold)*nums[i+4])==24)
output.append (nums[i]+" + ("+nums[i+1]+" / "+nums[i+3]+") * "+nums[i+4] + " = 24");
else if (((nums[i]+fHold)-nums[i+4])==24)
output.append (nums[i]+" + ("+nums[i+1]+" / "+nums[i+3]+") - "+nums[i+4] + " = 24");
else value++;
fHold=nums[i+1]+nums[i+3];
if (((nums[i]*fHold)/nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" + "+nums[i+3]+") / "+nums[i+4] + " = 24");
else if (((nums[i]*fHold)-nums[i+4])==24)
output.append (nums[i]+" * ("+nums[i+1]+" + "+nums[i+3]+") - "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)-nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" + "+nums[i+3]+") - "+nums[i+4] + " = 24");
else if (((nums[i]/fHold)*nums[i+4])==24)
output.append (nums[i]+" / ("+nums[i+1]+" + "+nums[i+3]+") * "+nums[i+4] + " = 24");
else value++;
if (value == 192){
output.append("There is no solution for this set of numbers");
this.i ++;
}
position ++;
eHold=nums[i+3];
nums[i+3]=nums[i+4];
nums[i+4]=eHold;
}
position ++;
eHold=nums[i+1];
nums[i+1]=nums[i+3];
nums[i+3]=nums[i+4];
nums[i+4]=eHold;
}
position ++;
eHold=nums[i];
nums[i]=nums[i+1];
nums[i+1]=nums[i+3];
nums[i+3]=nums[i+4];
nums[i+4]=eHold;
}
public static void main(String[]args){
java.util.Scanner input = new java.util.Scanner(System.in);
System.out.println("Enter 4 numbers between 1 - 9");
double w,x,y,z;
Game Player1 = new Game();
w = input.nextDouble();
x = input.nextDouble();
y = input.nextDouble();
z = input.nextDouble();
input.close();
Player1.Solve(w,x,y,z);
}
}
答案 0 :(得分：0)
Stringbuffer并不能真正让你删除内容（确实如此，但不是逐行删除） 你可能最好创建一个添加线条的Set。请注意，这是无序的，可能并不理想，但它将保证您不会两次打印相同的字符串。