怎么算，救命

[u011603343]

用1 2 8 10 怎么算做24点

[测试NULL]

#include <iostream>
#include <vector>
#include <cmath>
using namespace std;

const double MIN=1E-6;
void Print(int *Rank,double *FourNum)
{
    for(int i=0;i<4;i++)
        cout<<FourNum[Rank[i]]<<" ";
    cout<<endl;
}
void Calculate_24(int *Rank,double *FourNum,char *Oper,int i,int j,int k,bool &def)
{
    double res=0;
    switch(i)
    {
        case 0:
            res=FourNum[Rank[0]]+FourNum[Rank[1]];
            break;
        case 1:
            res=FourNum[Rank[0]]-FourNum[Rank[1]];
            break;
        case 2:
            res=FourNum[Rank[0]]*FourNum[Rank[1]];
            break;
        case 3:
            res=FourNum[Rank[0]]/FourNum[Rank[1]];
            break;
    }
    switch(j)
    {
        case 0:
            res=res+FourNum[Rank[2]];
            break;
        case 1:
            res=res-FourNum[Rank[2]];
            break;
        case 2:
            res=res*FourNum[Rank[2]];
            break;
        case 3:
            res=res/FourNum[Rank[2]];
            break;
    }
    switch(k)
    {
        case 0:
            res=res+FourNum[Rank[3]];
            break;
        case 1:
            res=res-FourNum[Rank[3]];
            break;
        case 2:
            res=res*FourNum[Rank[3]];
            break;
        case 3:
            res=res/FourNum[Rank[3]];
            break;
    }
    if(fabs(res-24)>MIN)
        return;
    else
    {
        def=true;
        for(int num=1;num<=7;num++)
        {
            switch(num)
            {
                case 1:
                    cout<<FourNum[Rank[0]];
                    break;
                case 3:
                    cout<<FourNum[Rank[1]];
                    break;
                case 5:
                    cout<<FourNum[Rank[2]];
                    break;
                case 7:
                    cout<<FourNum[Rank[3]];
                    break;
                case 2:
                    cout<<Oper[i];
                    break;
                case 4:
                    cout<<Oper[j];
                    break;
                case 6:
                    cout<<Oper[k];
                    break;
            }
        }
        cout<<endl;
    }
}
void SearchTree(int Depth,int *Rank,double *FourNum,char *Oper,bool &def)
{
    int i,j,k;
    if(Depth==4)
    {
        for(i=0;i<4;i++)
            for(j=0;j<4;j++)
                for(k=0;k<4;k++)
                    Calculate_24(Rank,FourNum,Oper,i,j,k,def);
    }
    else
    {
        for(i=0;i<4;i++)
        {
            int Remember=0;
            for(j=0;j<Depth;j++)
            {
                if(Rank[j]==i)
                    Remember=1;
            }
            if(Remember)
                continue;
            Rank[Depth]=i;
            SearchTree(Depth+1,Rank,FourNum,Oper,def);
        }
    }
}

int main(int argc, char *argv[])
{
    double a[4] = {1,2,8,10};
    int b[4];
    char c[4]={'+','-','*','/'};
    bool def=false;
    cout<<"所有可能的结果："<<endl;
    SearchTree(0,b,a,c,def);
    if(def==false)
        cout<<"No Solution!"<<endl;
    return 0;
}

[FancyMouse]

((8 - 1) * 2) + 10

[faoyy]

12 * (-8+10) = 24

[qzf362269994]

http://bbs.csdn.net/topics/380157851

[sjhcsdn]

算24 还是挺好玩的