#include<iostream>
using namespace std;

typedef struct _status{
    int lm, lc, rm, rc, steps;
    int m, c;//记录上次移动的，不返回上一步（简单剪枝）
    bool left;
    int pre;
}status;


class route{

public:
static const int maxsize = 100000;
status s1[maxsize];//状态队列
int front, rear;//队列的头尾指针
int n, steps;//记录船的容量 以及 最后的步数
bool find;

//初始化，插入第一个状态节点
void init(int m, int n1){
    rear = 0;
    front = 0;
    s1[0].lm = m;
    s1[0].lc = m;
    s1[0].rm = 0;
    s1[0].rc = 0;
    s1[0].m = 0;
    s1[0].c = 0;
    s1[0].steps = 0;
    s1[0].left = true;
    s1[0].pre = -1;
    steps = -1;
    n = n1;
    rear++;
    find = false;
}//end of function init()

void init(int m, int c, int n1){
    rear = 0;
    front = 0;
    s1[0].lm = m;
    s1[0].lc = c;
    s1[0].rm = 0;
    s1[0].rc = 0;
    s1[0].m = 0;
    s1[0].c = 0;
    s1[0].steps = 0;
    s1[0].left = true;
    s1[0].pre = -1;
    steps = -1;
    n = n1;
    rear++;
    find = false;
}//end of function init()

void in(status a1){
    if(rear >= maxsize - 1){//满队列，认为无解
        cout << "Queue overflow" << endl;
        find = true;
        steps = -1;
        a1.steps = -1;
    }
    s1[rear] = a1;
    rear ++;
}//end of function in()

status out(){
    front ++;
    return s1[front - 1];
}//end of function out()

void dump(){//测试输出所有遍历过的状态节点
    if(find){
        cout << "Find = true" << endl;
    }else{
        cout << "Find = false" << endl;
    }
    for(int i = 0; i < rear; i++){
        cout << i << ". " << "Step=" << s1[i].steps << "  " << s1[i].lm << " " << s1[i].lc;
        cout << " |";
        if(s1[i].left){
            cout << "<=>    | ";
        }else{
            cout << "    <=>| ";
        }
        cout << s1[i].rm << " " << s1[i].rc << " ,  pre=" << s1[i].pre <<endl;
    }
}//end of function dump()

void dump(status a1, char str = '~'){//测试输出一个节点
    cout << str << "  " << "Step=" << a1.steps << "  " << a1.lm << " " << a1.lc;
    cout << " |";
    if(a1.left){
        cout << "<=>    | ";
    }else{
        cout << "    <=>| ";
    }
    cout << a1.rm << " " << a1.rc << " ,  pre=" << a1.pre <<endl;
}//end of function dump(status a1)

void go(status a1, int m, int c){//探测当前节点的下一个状态
    if(a1.m == m && a1.c == c){
        return;//剪枝，不回到上一状态
    }
    if(a1.left){//船在左边
        a1.left = false;
        a1.lm -= m;
        a1.lc -= c;
        a1.rm += m;
        a1.rc += c;
    }else{//船在右边
        a1.left = true;
        a1.lm += m;
        a1.lc += c;
        a1.rm -= m;
        a1.rc -= c;
    }
    a1.m = m;
    a1.c = c;
    if(a1.lm > 0 && a1.lm < a1.lc || a1.lm < 0 || a1.lc < 0){//不符合条件
        return;
    }
    if(a1.rm > 0 && a1.rm < a1.rc || a1.rm < 0 || a1.rc < 0){//不符合条件
        return;
    }
    a1.pre = front - 1;//记录上一节点的位置
    if(a1.lm == 0 && a1.lc == 0){//找到路径
        //dump(a1);
        find = true;
        steps = a1.steps;
    }
    in(a1);//插入状态节点
}//end of function go()

private:
void find_route(int i){//递归输出路径
    if(s1[i].pre != -1){
        find_route(s1[i].pre);
        dump(s1[i], '~');
    }else{
        dump(s1[i], 'S');
    }
}
public:
void dump_route(){//供外部调用输出路径
    find_route(rear - 1);
}

};//end of class route;

int main(){
    int cases;
    int m, c, n;
    route r1;
    scanf("%d", &cases);
    while(cases--){
        status cur;
        //scanf("%d%d", &m, &n);
        //r1.init(m, n);
        scanf("%d%d%d", &m, &c, &n);
        r1.init(m, c, n);
        while(r1.front < r1.rear && r1.find == false){
            cur = r1.out();
            cur.steps ++;
            for(int m = n; m >= n / 2; m--){
                for(int c = 1; c <= n; c++){
                    r1.go(cur, 0, c);
                    if(r1.find)break;
                }
                for(int c = 0; c <= n - m; c++){
                    r1.go(cur, m, c);
                    if(r1.find)break;
                }
                if(r1.find)break;
            }
        }
        if(r1.find && r1.steps != -1){
            r1.dump_route();//输出路径
            cout << r1.steps << endl;
        }else{
            cout << "-1" << endl;
        }
    }
    return 0;
}