#include <iostream>
using namespace std;
int main(){
    int n;  cin >> n;
    while(n -- ){
        int l, r;   cin >> l >> r;
        int maxv = max(l, r);
        l += r, r = maxv, l -= r;
        int sum = 0;
        for(int i = l + 1; i < r; i ++ ){
            if(i % 2)   sum += i;
        }
        cout << sum << endl;
    }
    return 0;
}