算法之枚举

[jyzwf]

枚举法就是从所有候选答案中搜索出正确的解，满足两个条件：

1. 可预先确定候选答案的数量
2. 候选答案的范围在求解之前必须要有一个确定的集合

demo

将数字带入下面式子，使等式成立：

code

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int a1,a2,a3,a4,a5;
    long multi,result;
    for(a1=1;a1<=9;a1++)
    {
           for(a2=0;a2<=9;a2++)
           {
                  for(a3=0;a3<=9;a3++)
                  {
                         for(a4=0;a4<=9;a4++)
                         {
                                for(a5=0;a5<=9;a5++){
                                   multi = a1*10000 + a2*1000 + a3*100 + a4*10 + a5;
                                   result = a5*100000 + a5*10000 + a5*1000 + a5*100 + a5*10 + a5;
                                   if(multi*a1 == result){
                                          printf("\n%5d%2d%2d%2d%2d\n",a1,a2,a3,a4,a5);
                                          printf("X%12d\n",a1);
                                          printf("_____________\n");
                                          printf("%3d%2d%2d%2d%2d%2d",a5,a5,a5,a5,a5,a5);
                                   }
                                }
                         }
                  }
           }
    }

    getch();
    return 0;
}

result