1 //dp[i]=dp[j]+M+(sum[i]-sum[j])^2
 2 //设k<j<i, j比k决策好
 3 //dp[j]+M+(sum[i]-sum[j])^2<dp[k]+M+(sum[i]-sum[k])^2
 4 //(dp[j]+num[j]^2-(dp[k]+num[k]^2))/(2*(num[j]-num[k]))<sum[i]
 5 //dp[j]+num[j]^2-(dp[k]+num[k]^2))  GetUp()
 6 //2*(num[j]-num[k])  GetDown()
 7 #include <algorithm>
 8 #include <iostream>
 9 #include <cstring>
10 #include <cstdlib>
11 #include <cstdio>
12 #include <vector>
13 #include <ctime>
14 #include <queue>
15 #include <list>
16 #include <set>
17 #include <map>
18 using namespace std;
19 #define INF 0x3f3f3f3f
20 typedef long long LL;
21 
22 int dp[500010], n, m, sum[500010], q[500010];
23 int GetDp(int i, int j)
24 {
25     return dp[j] + m + (sum[i]-sum[j])*(sum[i]-sum[j]);
26 }
27 int GetUp(int j, int k)//yj-yk的部分
28 {
29     return dp[j] + sum[j]*sum[j] - (dp[k]+sum[k]*sum[k]);
30 }
31 int GetDown(int j, int k)//xj-xk的部分
32 {
33     return 2 * (sum[j] - sum[k]);
34 }
35 int main()
36 {
37     while(~scanf("%d %d", &n, &m))
38     {
39         sum[0] = dp[0] = 0;
40         for(int i = 1; i <= n; i++){
41             scanf("%d", &sum[i]);
42             sum[i] += sum[i-1];
43         }
44         int head = 0, tail = 0;
45         q[tail++] = 0;
46         for(int i = 1; i <=n; i++)
47         {
48             while(head+1<tail && GetUp(q[head+1],q[head])<=sum[i]*GetDown(q[head+1],q[head]))
49                 head++;
50             dp[i] = GetDp(i, q[head]);
51             while(head+1<tail && GetUp(i, q[tail-1])*GetDown(q[tail-1],q[tail-2])<=GetUp(q[tail-1],q[tail-2])*GetDown(i,q[tail-1]))
52                 tail--;
53             q[tail++] = i;
54         }
55         printf("%d\n", dp[n]);
56     }
57     return 0;
58 }