输入挂

int read() //代替scanf，速度更快，俗称输入挂{char ch=' ';int ans=0;while(ch<'0' || ch>'9')ch=getchar();while(ch<='9' && ch>='0'){ans=ans*10+ch-'0';ch=getchar();}return ans;}int n = read();

输出挂

void out(int a) //代替printf，速度更快，俗称输出挂{if(a > 9){out(a/10);}putchar(a%10 + '0');}out(n);