1.求2+22+222+2222+…+22…22(精确计算).

#include<stdio.h>
#define m 200
main()
{   
        long a[m],b,d;   
         int n,i,j,r;   
         printf("please input the number:");   
         scanf("%d",&n);   
         for(i=1;i<=m;i++)     
         a[i]=0;   
         d=0;   
         r=n;  
          for(i=1;i<=n;i++,r--)    
        {     for(j=1;j<=r;j++)        
              {       b=a[j]+d+2;        
                         a[j]=b%10;       
                          d=b/10;        
                }     
                 if(d>0)       
                  {   a[j]=a[j]+d;      
                          d=0;     
                  }   
          }   
          printf("2(%d)=",n);   
          for(i=n;i>=1;i--)   
         {     if(i%9==0)  
                 printf("/t");     
            printf("%ld",a[i]);  
           }   
            getch();
}