#include<iostream>
using namespace std;
int main(){
int n;
cin >> n;
int x,y;
while(true){
int sum = 0;
if(n == 0){
break;
}
cin >> x >> y;
if(x>y) swap(x,y);
for(x = x + 1;x < y;x++){
if(x % 2 == 1 || x%2 == -1) //判断奇数还得判断是否等于-1,比如-833%2 == -1
sum = sum + x;
}
cout << sum<< endl;
n--;
}
return 0;
}