template<typename T>
inline void read(T &x){ 
	x=0;
	register int f=1;
	register char c=getchar();
	while(!isdigit(c)){
		if(c=='-')f=-1;
		c=getchar();
	}
	while(isdigit(c)){
		x=x*10+c-'0';
		c=getchar();
	}
	x*=f;
}
template<typename T, typename ... Args>
inline void read(T &x, Args &... y){ 
	read(x);
	read(y...); 
}




ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);

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