#include <iostream>
using namespace std;
int main() {
int T;
cin >> T;
while (T--) {
long long L, R;
cin >> L >> R;
// 计算区间[L, R]中奇数的个数
long long count = (R - L + 2) / 2;
if ((L % 2 == 0) && (R % 2 == 0)) {
count = (R - L) / 2;
}
cout << count << endl;
}
return 0;
}
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