#include<iostream>
#include<math.h>
int g_count=0;
using namespace std;
void makefuhao(int x,int y[]);
void makenumbers(int& x1,int& x2,int& x3,int& x4,int n);
float makeresult(float x,float y,int z);
void makeshowout(int x1,int x2,int x3,int x4,int y[],int n);
int main()
{
int x1,x2,x3,x4;
char check;
int fuhao[3]={0};
float result[5]={0};
int num1,num2,num3,num4;
bool again=true;
bool wrong;
while(again)
{
do
{
cout<<"Input four numbers between 1 and 13!"<<endl;
cout<<"The first number :";
cin>>x1;
cout<<"The second number :";
cin>>x2;
cout<<"The third number :";
cin>>x3;
cout<<"The last number :";
cin>>x4;
wrong=false;
if(x1<1||x1>13||x2<1||x2>13||x3<1||x3>13||x4<1||x4>13)
{
cout<<"some number is not right!!"<<endl;
cout<<"please input four numbers again!"<<endl;
wrong=true;
}
}while(wrong);
for(int i=0;i<64;i++)
{
makefuhao(i,fuhao);
for(int j=0;j<24;j++)
{
num1=x1;
num2=x2;
num3=x3;
num4=x4;
makenumbers(num1,num2,num3,num4,j);
result[0]=makeresult(makeresult(num1,num2,fuhao[0]),makeresult(num3,num4,fuhao[2]),fuhao[1]);
result[1]=makeresult(makeresult(makeresult(num1,num2,fuhao[0]),num3,fuhao[1]),num4,fuhao[2]);
result[2]=makeresult(makeresult(num1,makeresult(num2,num3,fuhao[1]),fuhao[0]),num4,fuhao[2]);
result[3]=makeresult(num1,makeresult(makeresult(num2,num3,fuhao[1]),num4,fuhao[2]),fuhao[0]);
result[4]=makeresult(num1,makeresult(num2,makeresult(num3,num4,fuhao[2]),fuhao[1]),fuhao[0]);
for(int k=0;k<5;k++)
{
if(abs(result[k]-24.0)<0.00001) makeshowout(num1,num2,num3,num4,fuhao,k);
}
}
}
if(g_count==0) cout<<"You can't caculate 24 using these four numbers!"<<endl;
cout<<"If you want to try other numbers,press Y/y:";
cin>>check;
if(check=='y'||check=='Y') again=true;
else again=false;
g_count=0;
}
return 1;
}
void makefuhao(int x,int y[])
{
y[0]=x/32*2+x/4%2;
y[1]=x/16%2*2+x/2%2;
y[2]=x/8%2*2+x%2;
return;
}
float makeresult(float x,float y,int z)
{
switch(z)
{
case 0:
return x/(float)y;
case 1:
return x-y;
case 2:
return x*y;
case 3:
return x+y;
default:
cout<<"some wrong happens!"<<endl;
return 0;
}
}
void makenumbers(int& x1,int& x2,int& x3,int& x4,int n)
{
int tmp1=x1;
int tmp2=x2;
int tmp3=x3;
int tmp4=x4;
switch(n/6)
{
case 0:
x1=tmp1;
tmp1=tmp2;
tmp2=tmp3;
tmp3=tmp4;
break;
case 1:
x1=tmp2;
tmp1=tmp1;
tmp2=tmp3;
tmp3=tmp4;
break;
case 2:
x1=tmp3;
tmp1=tmp1;
tmp2=tmp2;
tmp3=tmp4;
break;
default:
x1=tmp4;
tmp1=tmp1;
tmp2=tmp2;
tmp3=tmp3;
break;
}
if(n/6==(n+4)/6)
{
x2=tmp1;
tmp1=tmp2;
tmp2=tmp3;
}
else if(n/6==(n+2)/6-1)
{
x2=tmp3;
tmp1=tmp1;
tmp2=tmp2;
}
else
{
x2=tmp2;
tmp1=tmp1;
tmp2=tmp3;
}
switch(n%2)
{
case 0:
x3=tmp1;
x4=tmp2;
break;
default:
x3=tmp2;
x4=tmp1;
break;
}
return;
}
void makeshowout(int x1,int x2,int x3,int x4,int y[],int n)
{
g_count++;
cout<<g_count<<":";
char chars[3];
for(int i=0;i<3;i++)
{
switch(y[i])
{
case 0:
chars[i]='/';
break;
case 1:
chars[i]='-';
break;
case 2:
chars[i]='*';
break;
default:
chars[i]='+';
break;
}
}
switch(n)
{
case 0:
cout<<"("<<x1<<chars[0]<<x2<<")"<<chars[1]<<"("<<x3<<chars[2]<<x4<<") = 24"<<endl;
break;
case 1:
cout<<"(("<<x1<<chars[0]<<x2<<")"<<chars[1]<<x3<<")"<<chars[2]<<x4<<" = 24"<<endl;
break;
case 2:
cout<<"(("<<x1<<chars[0]<<"("<<x2<<chars[1]<<x3<<"))"<<chars[2]<<x4<<" = 24"<<endl;
break;
case 3:
cout<<x1<<chars[0]<<"(("<<x2<<chars[1]<<x3<<")"<<chars[2]<<x4<<") =24"<<endl;
break;
default:
cout<<x1<<chars[0]<<"("<<x2<<chars[1]<<"("<<x3<<chars[2]<<x4<<")) =24"<<endl;
break;
}
return;
}
