快速读入外挂

针对n为10^5的数据有显著的作用，直接添加即可使用

namespace fastIO {
	#define BUF_SIZE 100000
	//fread -> read
	bool IOerror = 0;
	inline char nc() {
		static char buf[BUF_SIZE], *p1 = buf + BUF_SIZE, *pend = buf + BUF_SIZE;
		if(p1 == pend) {
			p1 = buf;
			pend = buf + fread(buf, 1, BUF_SIZE, stdin);
			if(pend == p1) {
				IOerror = 1;
				return -1;
			}
		}
		return *p1++;
	}
	inline bool blank(char ch) {
		return ch == ' ' || ch == '\n' || ch == '\r' || ch == '\t';
	}
	inline void read(int &x) {
		char ch;
		while(blank(ch = nc()));
		if(IOerror) return;
		for(x = ch - '0'; (ch = nc()) >= '0' && ch <= '9'; x = x * 10 + ch - '0');
	}
	#undef BUF_SIZE
};
using namespace fastIO;

inline void read(int &x){
    char ch;
    bool flag=false;
    for (ch=getchar();!isdigit(ch);ch=getchar())if (ch=='-') flag=true;
    for (x=0;isdigit(ch);x=x*10+ch-'0',ch=getchar());
    x=flag?-x:x;
}

inline void write(int x){
    static const int maxlen=100;
    static char s[maxlen];
        if (x<0) {   putchar('-'); x=-x;}
    if(!x){ putchar('0'); return; }
    int len=0; for(;x;x/=10) s[len++]=x % 10+'0';
    for(int i=len-1;i>=0;--i) putchar(s[i]);
};