题目就是求这个F(x)

题解：打个表找规律，F(x)=x/2-1+(sqrt(x)%2? 0:-1) 推荐证明：http://blog.csdn.net/acdreamers/article/details/9730423  

注：sqrt（）存在精度问题。精度处理不好会wa.

#include<cstdio>
#include<algorithm>
#include<iostream>
#include<cstring>
#include<cmath>
#define ll long long

using namespace std;


ll Sqrt(ll l,ll r,ll a) {
    ll mid=(l+r)/2;
    if(l>r)
        return r;
    if(a/mid>mid)
        return Sqrt(mid+1,r,a);
    else if(a/mid<mid)
        return Sqrt(l,mid-1,a);
    else
        return mid;
}

ll solve(ll r) {
    if(r<6)return 0;
    return r/2-2+(ll)Sqrt(1,r,r)%2;;
}

int main() {
    int t;
    cin>>t;
    while(t--) {
        ll l,r;
        scanf("%I64d%I64d",&l,&r);
        printf("%I64d\n",solve(r)-solve(l-1));
    }
    return 0;
}