奇技淫巧之节省输入输出时间

int Scan() { int res = 0, flag = 0; char ch; if((ch = getchar()) == '-') flag = 1; else if(ch >= '0' && ch <= '9') res = ch - '0'; while((ch = getchar()) >= '0' && ch <= '9') res = res * 10 + (ch - '0'); return flag ? -res : res; } void Out(int a) { if(a < 0) { putchar('-'); a = -a; } if(a >= 10) Out(a / 10); putchar(a % 10 + '0'); }//FROM YSF