int main(){
long l,cas;
char fir[MAX],sec[MAX],res[MAX];
scanf("%ld",&cas);
for(l=0;l<cas;l++){
scanf("%s%s",&fir,&sec);
if(call_minus(fir,sec,res)==1)
printf("-");
int len = strlen(res);
for(int i=0;i<len;i++)
printf("%c",res[i]);
printf("\n");
}
return 0;
}
void call_sqrt(char *number,char *result,char *extra){
int num,start,e,mul,l,r=0,len;
char left[MAX],after[MAX];
char who[5],temp[MAX],two[5];
len=strlen(number);
if(len%2==0){
num=10*(number[0]-'0') + number[1]-'0';
start=2;
}
else{
num=number[0]-'0';
start=1;
}
mul=(int) sqrt(num);
result[0]=mul+'0';
result[1]='\0';
if(num-mul*mul ==0)
extra[0]='\0';
else
sprintf(extra,"%d",num-mul*mul);
for(;start<len;start+=2){
e=strlen(extra);
extra[e]=number[start];
extra[e+1]=number[start+1];
extra[e+2]='\0';
two[0]='2';
two[1]='\0';
call_mult(result,two,left);
l=strlen(left);
for(mul=9;mul>=0;mul--){
who[0]=mul+'0';
who[1]='\0';
strcat(left,who);
call_mult(left,who,after);
if(call_minus(extra,after,temp)==1){
result[++r]=mul+'0';
result[r+1]='\0';
strcpy(extra,temp);
break;
}
else
left[l]='\0';
}
}
result[++r]='\0';
}
