7242: CodeChef MANYSUMS - Distinct Pair Sums
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Description
You are given a range of integers $\{L, L+1, \ldots, R\}$. An integer X is said to be reachable if it can be represented as a sum of two not necessarily distinct integers in this range.
Find the number of distinct reachable integers.
Find the number of distinct reachable integers.
Input
The first line of the input contains a single integer T denoting the number of test cases. The description of T test cases follows.
The first and only line of each test case contains two space-separated integers L and R.
The first and only line of each test case contains two space-separated integers L and R.
Output
For each test case, print a single line containing one integer — the number of reachable integers.
Constraints
$1≤T≤10^5$
$1 \leq L \leq R \leq 10^6$
$1 \leq L \leq R \leq 10^6$
Sample 1 Input
2
2 2
2 3
Sample 1 Output
1
3
Example case 1: The only reachable integer is 2 + 2 = 4.
Example case 2: 4, 5 and 6 are reachable, since 2+2=4, 2+3=5 and 3+3=6.
Example case 2: 4, 5 and 6 are reachable, since 2+2=4, 2+3=5 and 3+3=6.