链接：Simple Math Problem | JXNUOJ
Tongtong is playing math game again. She had come across this square matrix many times,so needless to say, she knows what you want to ask. Now she throws this question to you. You need to look at the following square matrix,then she will give you three integers n,x,and y,that means there are an n×n square matrix.
You need to figure out what the value of row x, column y corresponds to.
For example,there are one 5×5 square matrix:
她需要通过这个矩阵。你需要看着以下这个矩阵，她会给你三个数，n,x,y,意味着这是个n*n的方形迷宫。需要算出行x列y这个坐标对应的值。
0 1 3 6 A
2 4 7 B F
5 8 C 10 13
9 D 11 14 16
E 12 15 17 18
输入：
Only a single line contains three integers n,x,y(0≤x≤1000000000,0≤y≤1000000000,1≤n≤1000000001)n,x,y(0≤x≤1000000000,0≤y≤1000000000,1≤n≤1000000001)
输入n,x,y,
输出：
A single line with an integer representing the corresponding value.
输出一个数表示对应的值。
输入：5 2 2
输出：12 表示第二行第二列对应12
