1 inline int readint() 2 { 3     char c = getchar(); 4     while(!isdigit(c))  c = getchar(); 5  6     int x = 0; 7     while(isdigit(c)) 8     { 9         x = x*10+c-‘0‘;10         c = getchar();11     }12     return x;13 }14 15 int buf[10];16 inline void writeint(int i)17 {18     int p = 0;19     if(i == 0)  p++;20     else21         while(i)22     {23         buf[p++] = i%10;24         i /= 10;25     }26     for(int j = p-1; j >= 0; j--)27     {28         putchar(buf[j]+‘0‘);29     }30 }