#dpz. [dp_z]Frog 3

[dp_z]Frog 3

Problem Statement

There are NN stones, numbered 1,2,ldots,N1, 2, \\ldots, N. For each ii (1leqileqN1 \\leq i \\leq N), the height of Stone ii is hih_i. Here, h1<h2<cdots<hNh_1 < h_2 < \\cdots < h_N holds.

There is a frog who is initially on Stone 11. He will repeat the following action some number of times to reach Stone NN:

  • If the frog is currently on Stone ii, jump to one of the following: Stone i+1,i+2,ldots,Ni + 1, i + 2, \\ldots, N. Here, a cost of (hjhi)2+C(h_j - h_i)^2 + C is incurred, where jj is the stone to land on.

Find the minimum possible total cost incurred before the frog reaches Stone NN.

Constraints

  • All values in input are integers.
  • 2leqNleq2times1052 \\leq N \\leq 2 \\times 10^5
  • 1leqCleq10121 \\leq C \\leq 10^{12}
  • 1leqh1<h2<cdots<hNleq1061 \\leq h_1 < h_2 < \\cdots < h_N \\leq 10^6

Input

Input is given from Standard Input in the following format:

NN CC h1h_1 h2h_2 ldots\\ldots hNh_N

Output

Print the minimum possible total cost incurred.


Sample Input 1

5 6
1 2 3 4 5

Sample Output 1

20

If we follow the path 113355, the total cost incurred would be ((31)2+6)+((53)2+6)=20((3 - 1)^2 + 6) + ((5 - 3)^2 + 6) = 20.


Sample Input 2

2 1000000000000
500000 1000000

Sample Output 2

1250000000000

The answer may not fit into a 32-bit integer type.


Sample Input 3

8 5
1 3 4 5 10 11 12 13

Sample Output 3

62

If we follow the path 1122445588, the total cost incurred would be $((3 - 1)^2 + 5) + ((5 - 3)^2 + 5) + ((10 - 5)^2 + 5) + ((13 - 10)^2 + 5) = 62$.