【黑科技】读写优化 orz bdd

转自 bdd ：http://www.cnblogs.com/kevince/p/3924688.html

读入优化：

 inline int read()
 {
     char ch;
     bool flag = false;
     int a = 0;
     while(!((((ch = getchar()) >= '0') && (ch <= '9')) || (ch == '-')));
     if(ch != '-')
     {
         a *= 10;
         a += ch - '0';
     }
     else
     {
         flag = true;
     }
     while(((ch = getchar()) >= '0') && (ch <= '9'))
     {
         a *= 10;
         a += ch - '0';
     }
     if(flag)
     {
         a = -a;
     }
     return a;
 }

输出优化：

void write(int a)
{
    if(a < 0)
    {
        putchar('-');
        a = -a;
    }
    if(a >= 10)
    {
        write(a / 10);
    }
    putchar(a % 10 + '0');
    putchar('
');
}