题目描述
Find the minimum height of a rooted tree$^{\dagger}$ with $a+b+c$ vertices that satisfies the following conditions:
- $a$ vertices have exactly $2$ children,
- $b$ vertices have exactly $1$ child, and
- $c$ vertices have exactly $0$ children.
The tree above is rooted at the top vertex, and each vertex is labeled with the number of children it has. Here $a=2$, $b=1$, $c=3$, and the height is $2$.
$^{\dagger}$ A rooted tree is a connected graph without cycles, with a special vertex called the root. In a rooted tree, among any two vertices connected by an edge, one vertex is a parent (the one closer to the root), and the other one is a child.
The distance between two vertices in a tree is the number of edges in the shortest path between them. The height of a rooted tree is the maximum distance from a vertex to the root.
Input
The first line contains an integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases.
The only line of each test case contains three integers $a$, $b$, and $c$ ($0 \leq a, b, c \leq 10^5$; $1 \leq a + b + c$).
The sum of $a + b + c$ over all test cases does not exceed $3 \cdot 10^5$.
Output
For each test case, if no such tree exists, output $-1$. Otherwise, output one integer — the minimum height of a tree satisfying the conditions in the statement.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
样例输出
提示
The first test case is pictured in the statement. It can be proven that you can't get a height smaller than $2$.
In the second test case, you can form a tree with a single vertex and no edges. It has height $0$, which is clearly optimal.
In the third test case, you can form a tree with two vertices joined by a single edge. It has height $1$, which is clearly optimal.