#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define bll __int128
#define pb push_back
#define ppb pop_back
#define mp make_pair
#define fi first
#define sec second
#define vii vector<int>
#define pll pair<ll,ll>
#define vll vector<ll>
#define pii pair<int,int>
#define pil pair<int,ll>
#define re register
#define puu pair<ull,ull>
#define clr clear
#define vpi vector<pii>
#define qii queue<int>
using namespace std;
namespace io{
	const int __SIZE=(1<<22)+1;
	char ibuf[__SIZE],*iS,*iT,obuf[__SIZE],*oS=obuf,*oT=oS+__SIZE-1,__c,qu[55];int __f,qr,_eof;
#define Gc()(iS==iT?(iT=(iS=ibuf)+fread(ibuf,1,__SIZE,stdin),(iS==iT?EOF:*iS++)):*iS++)
	inline void flush(){fwrite(obuf,1,oS-obuf,stdout),oS=obuf;}
	inline void gc(char&x){x=Gc();}
	inline void pc(char x){*oS++=x;if(oS==oT)flush();}
	inline void pstr(const char*s){int __len=strlen(s);for(__f=0;__f<__len;++__f)pc(s[__f]);}
	inline void gstr(char*s){for(__c=Gc();__c<32||__c>126||__c==' ';)__c=Gc();
		for(;__c>31&&__c<127&&__c!=' ';++s,__c=Gc())*s=__c;*s=0;}
	template<class I>inline bool read(I&x){_eof=0;
		for(__f=1,__c=Gc();(__c<'0'||__c>'9')&&!_eof;__c=Gc()){if(__c=='-')__f=-1;_eof|=__c==EOF;}
		for(x=0;__c<='9'&&__c>='0'&&!_eof;__c=Gc())x=x*10+(__c&15),_eof|=__c==EOF;x*=__f;return!_eof;}
	template<class I>inline void write(I x){if(!x)pc('0');if(x<0)pc('-'),x=-x;
		while(x)qu[++qr]=x%10+'0',x/=10;while(qr)pc(qu[qr--]);}
	struct Flusher_{~Flusher_(){flush();}}io_flusher_;
}using io::pc;using io::gc;using io::pstr;using io::gstr;using io::read;using io::write;
const int N=1e6+5;
int n,m,T;
ll x;
string str;
struct Big{
	int a[N],len;
	void pre(){memset(a,0,sizeof(a)),len=0;}
	void chk()
	{
		for(int i=1;i<=len;i++)
		{
			if(a[i]>=10)
			{
				a[i+1]+=a[i]/10,a[i]%=10;
				if(i==len)len++;
			}
			if(a[i]<0)a[i+1]--,a[i]+=10;
		}
		while(a[len]==0)len--;
	}
	void get(ll x){memset(a,0,sizeof(a)),len=0;while(x)a[++len]=x%10,x/=10;}
	void print(){for(int i=len;i>=1;i--)cout<<a[i];cout<<'\n';}
}a,b[35];
Big z,oo;
const Big & operator +(const Big&x,const Big&y)
{
	z.pre(),z.len=max(x.len,y.len);
	for(int i=1;i<=max(x.len,y.len);i++)z.a[i]=x.a[i]+y.a[i];
	z.chk();return z;
}
const Big & operator +(const Big&x,int y)
{
	static Big Y;Y.get(y);
	return (x+Y);
}
const Big & operator -(const Big&x,const Big&y)
{
	z.pre(),z.len=max(x.len,y.len);
	for(int i=1;i<=max(x.len,y.len);i++)z.a[i]=x.a[i]-y.a[i];	
	z.chk();return z;
}
const Big & operator -(const Big&x,int y)
{
	static Big Y;Y.get(y);
	return x-Y;
}
const Big & operator *(const Big&x,const Big&y)
{
	z.pre(),z.len=x.len+y.len-1;
	for(int i=1;i<=x.len;i++)for(int j=1;j<=y.len;j++)z.a[i+j-1]+=x.a[i]*y.a[j];
	z.chk();return z;
}
const Big & operator *(const Big&x,int y)
{
	z.pre(),z.len=x.len;
	for(int i=1;i<=x.len;i++)z.a[i]=x.a[i]*y;
	z.chk();return z;
}
const Big & operator /(const Big&x,int y)
{
	z.pre(),z.len=x.len;
	int res=0;
	for(int i=x.len;i>=1;i--)res=res*10+x.a[i],z.a[i]=res/y,res%=y;
	z.chk();return z;
}
bool operator<(const Big&x,const Big&y)
{
	if(x.len!=y.len)return x.len<y.len;
	for(int i=x.len;i>=1;i--)if(x.a[i]!=y.a[i])return x.a[i]<y.a[i];
	return false;
}
bool operator<=(const Big&x,const Big&y)
{
	if(x.len!=y.len)return x.len<y.len;
	for(int i=x.len;i>=1;i--)if(x.a[i]!=y.a[i])return x.a[i]<y.a[i];
	return true;
}
bool operator>(const Big&x,const Big&y)
{
	if(x.len!=y.len)return x.len>y.len;
	for(int i=x.len;i>=1;i--)if(x.a[i]!=y.a[i])return x.a[i]>y.a[i];
	return false;
}
bool operator>=(const Big&x,const Big&y)
{
	if(x.len!=y.len)return x.len>y.len;
	for(int i=x.len;i>=1;i--)if(x.a[i]!=y.a[i])return x.a[i]>y.a[i];
	return true;
}
int count(int x)
{
	int s=0;
	while(x)x/=10,s++;
	return s;
}
int main()
{
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	cin>>T;
	while(T--)
	{
		cin>>str>>m,n=str.length(),x=0,a.len=n;
		int len=0,c=count(m);
		Big now;now.get(m);
		for(int i=1;i<=n;i++)a.a[i]=str[n-(i-1)-1]-'0';
		a=a+1;
		if(a<now){now.print();continue;}
		for(int i=n;i>=1;i--)x=x*10+a.a[i],x%=m;
		b[++len]=a+(int)(m-x)%m;
		int bbzz=0;
		for(int i=c;i<=n;i++)
		{
			int bz=0;
			for(int j=i;j>=i-c+1;j--)if(now.a[j-(i-c+1)+1]!=a.a[j]){bz=1;break;}
			if(bz)continue;
			bbzz=1;
		}
		if(bbzz){a.print();continue;}
		for(int i=c;i<=n&&len<=2*c+2;i++)
		{
			int bz=0;
			for(int j=i;j>=i-c+1;j--)
			{
				if(now.a[j-(i-c+1)+1]<a.a[j]){bz=1;break;}
				else if(now.a[j-(i-c+1)+1]>a.a[j])break;
			}
			if(!bz)
			{
				b[++len]=a;	
				for(int j=i;j>=i-c+1;j--)b[len].a[j]=now.a[j-(i-c+1)+1];
				for(int j=i-c;j>=1;j--)b[len].a[j]=0;
			}
		}
		Big A;A.len=1e9;
		for(int i=1;i<=len;i++)if(A>b[i])A=b[i];
		A.print();
	}
}