//大数除法(当被除数比除数要小的时候直接取0)
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define N 200
int Substract(int num1[],int num2[],int n1,int n2)
{
int i;
if(n1 < n2)
return -1;
if(n1 == n2)
for(i = n1-1; i >= 0; i--)
if(num1[i] > num2[i])
break;
else if(num1[i] < num2[i])
return -1;//num1比num2小的时候就返回-1
for(i = 0; i < n1; ++i)
{
num1[i] -= num2[i];
if(num1[i] < 0)
{
num1[i] += 10;
--num1[i+1];
}
}
for(i = n1-1; i >= 0; --i)
if(num1[i] > 0)
return i+1;
return 0;
}
int main()
{
int i,e,j;
char s1[N+10],s2[N+10];
int num1[N+10],num2[N+10],num[N+10],n1,n2,n,flag,times;
scanf("%d",&n);
getchar();
while(n--)
{
scanf("%s %s",s1,s2);
memset(num1,0,sizeof(num1));
memset(num,0,sizeof(num));
memset(num2,0,sizeof(num2));
n1 = strlen(s1);
n2 = strlen(s2);
if(n1 < n2)
{
printf("0\n");
continue;
}
for(i = n1-1,e = -1; i >= 0; --i)
num1[++e] = s1[i] - '0';
for(i = n2 -1,e = -1; i >= 0; --i)
num2[++e] = s2[i] - '0';
times = n1-n2;
if(times > 0)
{
for(i = n1-1; i >= times; --i)
num2[i] = num2[i-times];
for(; i >= 0; --i)
num2[i] = 0;
n2 = n1;
}
for(i = 0; i <= times; ++i)
{
while((flag = (Substract(num1,num2+i,n1,n2-i)))>= 0)
{
n1 = flag;
++num[times-i];
}
}
for(i = N; i >= 0&&num[i] == 0; --i);
if(i == -1)
printf("*0\n");
else
{for(; i >= 0; --i)
printf("%d",num[i]);
putchar(10);
}
}
return 0;
}