这个快读会不会 RE 啊（如果会的话就tg1=不保了）

int read(){
	char c = getchar();
	int p = 1, x = 0;
	while (c == ' ' || c == '\n') c = getchar();
	if (c == '-') p = -1, c = getchar();
	while (c >= '0' && c <= '9'){
		x = (x << 1) + (x << 3) + (c ^ 48);
		c = getchar();
	}
	return x * p;
}