快读模板

其实用处不大 acm卡常没什么意思 原理就是getchar()很快

inline int read(){
    char ch = getchar(); int x = 0, f = 1;
    while(ch < '0' || ch > '9') {if(ch == '-') f = -1; ch = getchar();}
    while('0' <= ch && ch <= '9') {x = x * 10 + ch - '0'; ch = getchar();}
    return x * f;
}