#include <bits/stdc++.h>
using namespace std;
#define SIZE 123456
int main(void) {
int i = 0, j = 0,count = 0;
int prime[SIZE];
int my_prime[SIZE];
for(i=1; i < SIZE; ++i)
prime[i] = i;
for(i = 2; i < SIZE; ++i) {
if(prime[i]) {
my_prime[count++] = prime[i];
j = i + i;
for(; j < SIZE; j += i){
prime[j] = 0;
}
}
}
int T = 0;
scanf("%d",&T);
while(T--) {
int a = 0, b = 0;
scanf("%d %d",&a,&b);
int test = a - b;
unsigned long long int num = 1;
while(test--) {
num = num * a--;
}
int res = 0;
for(i = 0;i < count ;++i) {
while(num % my_prime[i] == 0) {
num /= my_prime[i];
}
++res;
if(num == 1)
break;
}
printf("%d\n",res);
}
return 0;
}
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