24点游戏算法

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#include <stdio.h>
#include <string.h>
#include <math.h>

#define LING    1E-6
#define CONT    4
#define VOLUE   24

float number[CONT];
char expression[CONT][20] ;
bool m_judge = false;                           //判断是否有解。
int count = 0;

void Find(int n)
{
    int i = 0, j = 0;

    if (n == 1)
    {
        if ( fabs(number[0] - 24) <= LING)
        {
            for (i = 0; i < 20; i++)
            {
                printf("%c", expression[0][i]) ;
            }
            printf("\t\t") ;
            m_judge = true;
            count ++;
            if((count % 2)==0)              //使输出时每行三个表达式
                printf("\n") ;
        }
        else
        { }
    }
    for(i = 0; i < n; i++)               //查找
    {
        for (j = i + 1; j < n; j++)      //与其后面的查找进行计算
        {
            float a, b;
            char expressiona[20], expressionb[20];

            a = number[i] ;
            b = number[j] ;
            number[j] = number[n - 1];

            strcpy(expressiona, expression[i]) ;
            strcpy(expressionb, expression[j]) ;
            strcpy(expression[j], expression[n - 1]) ;

            sprintf(expression[i], "(%s+%s)", expressiona, expressionb) ;
            number[i] = a + b;
            Find(n-1);

            ///////////////////////////////////
            sprintf(expression[i], "(%s-%s)", expressiona, expressionb) ;
            number[i] = a - b;
            Find(n-1);

            sprintf(expression[i], "(%s-%s)", expressionb, expressiona) ;
            number[i] = b - a;
            Find(n-1);

            sprintf(expression[i], "(%s*%s)", expressiona, expressionb) ;
            number[i] = a * b;
            Find(n-1);

            if (b != 0)
            {
                sprintf(expression[i], "(%s/%s)", expressiona, expressionb) ;
                number[i] = a / b;
                Find(n-1);
            }
            if (a != 0)
            {
                sprintf(expression[i], "(%s/%s)", expressionb, expressiona) ;
                number[i] = b / a;
                Find(n-1);
            }
            number[i] = a;                          // 最后一层的Find(2)调用完成后将a重新赋值给number[i]即number[0]
            number[j] = b;                          // 最后一层的Find(2)调用完成后将b重新赋值给nubmer[j]即number[1]
            strcpy(expression[i], expressiona) ;
            strcpy(expression[j], expressionb) ;
        }
    }
}
int main()
{
    int i, j ;
    printf("请输入四个数:\n") ;
    for (i = 0; i < CONT; i++)
    {
        char ch[20], s;
        int a ;
        printf("第%d个数:", i+1) ;
        scanf("%f", &number[i]) ;
        a = (int)number[i] ;
        s = char(a + 48);
        ch[0] = s ;
        for (j = 1; j < 20; j++)
        {
            ch[j] = 0 ;
        }
        strcpy(expression[i], ch) ;
    }

    printf("\n") ;
    Find(CONT) ;
    if(m_judge==true)
    {
        printf("\n\n成功!\n") ;
        printf("总共的计算方法共有:%d\n", count) ;
    }
    else
    {
        printf("失败!") ;
    }
    return 0;
}