//拓歐
void exgcd(long long  a,long long  b,long long &x,long long  &y)
{
	if(b == 0)
	{
		x = 1;
		d = a;
		y = 0;
		return ;
	}
	else
	{
		long long x0, y0;
		exgcd(b, a%b, x0, y0);
		x = y0;
		y = x0 - (a/b) * y0; 
	}
} 
long long  inverse(long long a,long long b)
{
	long long x = 0, y  = 0;
	exgcd(a,b,x,y);
	return (x % b + b) %b;
}//此處為中國剩餘定理裡面的。
 

費馬
long long mpow(int a,int b,int modd)
{
	int rt = 1;
	for( ; b; b >>= 1, a = (1ll * a * a)% modd)
	{
		if(b&1) rt = (1ll * rt * a) % modd;
	}
	return rt;
}
	int ici = mpow(ci, mod[i] - 2, mod[i]);

a*x≡1(mod p)

a*x + p*y = 1;