#include <iostream>
using namespace std;
int n,x,y,sum;
int main()
{
    cin>>n;
    while(n--){
        sum=0;
        cin>>x>>y;
        if(x>y) swap(x,y);
        for(int i=(x%2==0?x+1:x+2);i<y;i+=2) sum+=i;
        cout<<sum<<endl;
    }
}