#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
int main() {
int tc;
scanf("%d",&tc);
while(tc--){
unsigned long long n,p;
scanf("%llu%llu",&n,&p);
printf("%llu\n",n%p);
}
/* Enter your code here. Read input from STDIN. Print output to STDOUT */
return 0;
}
I2luY2x1ZGUgPHN0ZGlvLmg+CiNpbmNsdWRlIDxzdHJpbmcuaD4KI2luY2x1ZGUgPG1hdGguaD4KI2luY2x1ZGUgPHN0ZGxpYi5oPgppbnQgbWFpbigpIHsKICAgIGludCB0YzsKICAgIHNjYW5mKCIlZCIsJnRjKTsKICAgIHdoaWxlKHRjLS0pewogICAgICAgIHVuc2lnbmVkIGxvbmcgbG9uZyBuLHA7CiAgICAgICAgc2NhbmYoIiVsbHUlbGx1IiwmbiwmcCk7CiAgICAgICAgcHJpbnRmKCIlbGx1XG4iLG4lcCk7CiAgICB9CiAgICAKICAgIAogICAgLyogRW50ZXIgeW91ciBjb2RlIGhlcmUuIFJlYWQgaW5wdXQgZnJvbSBTVERJTi4gUHJpbnQgb3V0cHV0IHRvIFNURE9VVCAqLyAgICAKICAgIHJldHVybiAwOwp9Cg==