#include<cstdio>
#include<iostream>
#include<initializer_list>
namespace QL{
	namespace details{
		template<typename _Tp>
		static constexpr std::size_t integral_length=sizeof(_Tp)*10/sizeof(int);
#ifndef _GLIBCXX_TYPE_TRAITS
		template<typename _Tp>
		struct is_unsigned{constexpr operator bool(){return false;}};
		template<>
		struct is_unsigned<unsigned int>{constexpr operator bool(){return true;}};
		template<>
		struct is_unsigned<unsigned long>{constexpr operator bool(){return true;}};
		template<>
		struct is_unsigned<unsigned long long>{constexpr operator bool(){return true;}};
		template<>
		struct is_unsigned<unsigned __int128>{constexpr operator bool(){return true;}};
		template<>
		struct is_unsigned<unsigned char>{constexpr operator bool(){return true;}};
		template<typename _Tp>
		static constexpr bool is_unsigned_t=is_unsigned<_Tp>();
#else
		template<typename _Tp>
		static constexpr bool is_unsigned_t=std::is_unsigned<_Tp>();
#endif
	}
	namespace IO{
		using details::integral_length;
		using details::is_unsigned_t;
		class IO{
		protected:
#ifdef _INITIALIZER_LIST
			using LIST=std::initializer_list<int>;
#endif
#ifndef LOCAL
			FILE*IN;
			FILE*OUT;
			static constexpr int SIZE=1<<20;
			char buf[SIZE]{},*p1{},*p2{},obuf[SIZE]{},*p3{};
			char std_getchar(){return p1==p2&&(p2=(p1=buf)+fread(buf,1,SIZE,IN),p1==p2)?EOF:*p1++;}
			void std_putchar(char ch){(p3-obuf<SIZE)?(*p3++=ch):(out_end(),*p3++=ch);}
			template<std::size_t L>
			FILE*set_in(const char(&name)[L]){
				static char in[L+5]={};
				__builtin_memcpy(in,name,sizeof in);
				in[L-1]='.',in[L]='i',in[L+1]='n',in[L+2]='\0';
				return std::fopen(in,"r");
			}
			template<std::size_t L>
			FILE*set_out(const char(&name)[L]){
				static char out[L+5];
				__builtin_memcpy(out,name,sizeof out);
				out[L-1]='.',out[L]='o',out[L+1]='u',out[L+2]='t',out[L+3]='\0';
				return std::fopen(out,"w");
			}
#else
			char std_getchar(){return std::getchar();}
			void std_putchar(char ch){std::putchar(ch);}
			void err_putchar(char ch){std::fprintf(stderr,"%c",ch);}
			template<std::size_t L>
			void reset_stdin(const char(&name)[L]){
				static char in[L+5]={};
				__builtin_memcpy(in,name,sizeof in);
				in[L-1]='.',in[L]='i',in[L+1]='n',in[L+2]='\0';
				freopen(in,"r",stdin);
			}
			template<std::size_t L>
			void reset_stdout(const char(&name)[L]){
				static char out[L+5];
				__builtin_memcpy(out,name,sizeof out);
				out[L-1]='.',out[L]='o',out[L+1]='u',out[L+2]='t',out[L+3]='\0';
				freopen(out,"w",stdout);
			}
#endif
		public:
#ifndef LOCAL
			IO():IN(stdin),OUT(stdout),p1(buf),p2(buf),p3(obuf){}
			template<std::size_t L>
			IO(const char(&name)[L]):IN(set_in(name)),OUT(set_out(name)),p1(buf),p2(buf),p3(obuf){}
			template<std::size_t L>
			IO(const char(&name)[L],bool in,bool out):IN(in?set_in(name):stdin),OUT(out?set_out(name):stdout),p1(buf),p2(buf),p3(obuf){}
			~IO(){out_end();}
			void out_end(){__builtin_fwrite(obuf,p3-obuf,1,OUT),p3=obuf;}
#else
			IO(){}
			template<std::size_t L>
			IO(const char(&name)[L]){reset_stdin(name),reset_stdout(name);}
			template<std::size_t L>
			IO(const char(&name)[L],bool in,bool out){in&&(reset_stdin(name),0),out&&(reset_stdout(name),0);}
#endif
		    template<typename T>
		    void read(T&x){
		        x=0;bool flag=0;char ch=std_getchar();
		        for(;ch<'0'||ch>'9';ch=std_getchar()) if(ch=='-') flag=1;
		        if(flag) for(;ch>='0'&&ch<='9';ch=std_getchar()) x=(x<<1)+(x<<3)-(ch&15);
		        else for(;ch>='0'&&ch<='9';ch=std_getchar()) x=(x<<1)+(x<<3)+(ch&15);
		    }
		    template<typename T=int>
		    T read(){
		        T x=0;bool flag=0;char ch=std_getchar();
		        for(;ch<'0'||ch>'9';ch=std_getchar()) if(ch=='-') flag=1;
		        if(flag) for(;ch>='0'&&ch<='9';ch=std_getchar()) x=(x<<1)+(x<<3)-(ch&15);
		        else for(;ch>='0'&&ch<='9';ch=std_getchar()) x=(x<<1)+(x<<3)+(ch&15);
		        return x;
		    }
		    void read(char*str){
		        while((*str=std_getchar())==' '||*str=='\n');
		        while((*++str=std_getchar())!=' '&&*str!='\n');
		        *str=0;
		    }
		    void read(char&c){while((c=std_getchar()==' '||c=='\n'));}
		    template<typename T>
		    void write(T x){
		        static char sta[integral_length<T>];
		        int top=0;
				if(is_unsigned_t<T>){
		            do sta[top++]=(x%10)|48,x/=10;
		            while(x);
		    	}
				else{
			        if(x<0){
			            std_putchar('-');
			            do sta[top++]=((-x)%10)|48,x/=10;
			            while(x);
			        }
			        else{
			            do sta[top++]=(x%10)|48,x/=10;
			            while(x);
			        }
			    }
		        while(top) std_putchar(sta[--top]);
		    }
		    void write(char x){std_putchar(x);}
		    void write(char*str){while(*str!='\0') std_putchar(*str++);}
		    void write(const char *str){while(*str!='\0') std_putchar(*str++);}
#ifdef LOCAL
		    template<typename T>
		    void error(T x){
		        static char sta[integral_length<T>];
		        int top=0;
				if(is_unsigned_t<T>){
		            do sta[top++]=(x%10)|48,x/=10;
		            while(x);
		    	}
				else{
			        if(x<0){
			            err_putchar('-');
			            do sta[top++]=((-x)%10)|48,x/=10;
			            while(x);
			        }
			        else{
			            do sta[top++]=(x%10)|48,x/=10;
			            while(x);
			        }
			    }
		        while(top) err_putchar(sta[--top]);
		    }
		    void error(char x){err_putchar(x);}
		    void error(char*str){while(*str!='\0') err_putchar(*str++);}
		    void error(const char *str){while(*str!='\0') err_putchar(*str++);}
#endif
#ifdef _INITIALIZER_LIST
		    template<typename...Args>
		    void read(Args&...args){(void)LIST{(read(args),0)...};}
		    template<typename...Args>
		    void write(Args...args){(void)LIST{(write(args),0)...};}
		    template<typename...Args>
		    void writeln(Args...args){write(args...),std_putchar('\n');}
#ifdef LOCAL
		    template<typename...Args>
		    void error(Args...args){(void)LIST{(error(args),0)...};}
		    template<typename...Args>
		    void errorln(Args...args){error(args...),err_putchar('\n');}
#endif
#else
		    template<typename _Tp,typename...Args>
		    void read(_Tp&x,Args&...args){read(x),read(args...);}
		    void write(){}
		    template<typename _Tp,typename...Args>
		    void write(_Tp x,Args...args){write(x),write(args...);}
		    template<typename...Args>
		    void writeln(Args...args){write(args...),std_putchar('\n');}
#ifdef LOCAL
		    void error(){}
		    template<typename _Tp,typename...Args>
		    void error(_Tp x,Args...args){error(x),error(args...);}
		    template<typename...Args>
		    void errorln(Args...args){error(args...),err_putchar('\n');}
#endif
#endif
		};
	}
}
using namespace QL::IO;
IO lq;
constexpr int N=20;
using ull=unsigned long long;
ull f[N][N][2];
constexpr ull qw[N]{
	1ull,
	10ull,
	100ull,
	1000ull,
	10000ull,
	100000ull,
	1000000ull,
	10000000ull,
	100000000ull,
	1000000000ull,
	10000000000ull,
	100000000000ull,
	1000000000000ull,
	10000000000000ull,
	100000000000000ull,
	1000000000000000ull,
	10000000000000000ull,
	100000000000000000ull,
	1000000000000000000ull,
	10000000000000000000ull
},Inf=0x3f3f3f3f3f3f3f3f;
char n[N];
int len;
signed main(){
	for(int Test_Cases=lq.read();Test_Cases--;){
		ull x;
		int k;
		lq.read(x,k);
		static char sta[N]{};
		static int top{};
		top=0,len=1;
		while(x%10==0) sta[++top]='0',x/=10;
		while(x) n[len++]=(x%10)|48,x/=10;
		for(int i=len;i<N;++i) n[i]='0';
		__builtin_memset(f,0x3f,sizeof f);
		f[0][0][0]=0;
		for(int p=1;p<N;++p){
			for(int j=0;j<=k;++j){
				f[p][j][0]=f[p-1][j][0];
				if(n[p]!='9') f[p][j][0]=std::min(f[p][j][0],f[p-1][j][1]);
				if(j>=1){
					int least='9'-n[p];
					f[p][j][1]=least*qw[p-1]+f[p-1][j-1][1];
					++least;
					if(n[p]!='0') f[p][j][1]=std::min(f[p][j][1],least*qw[p-1]+f[p-1][j-1][0]);
				}
			}
		}
		ull ans=std::min(f[N-1][k][0],f[N-1][k][1]);
		if(k) lq.write(ans);
		else{
			int p=0;
			for(int i=1;i<len&&!p;++i) if(n[i]!='9') p=i;
			lq.write(p?qw[p-1]:qw[len-1]);
		}
		while(top) lq.write(sta[top--]);
		lq.writeln();
	}
	return 0;
}