1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstdlib>
 4 #include <cstring>
 5 #include <algorithm>
 6 #include <stack>
 7 #include <queue>
 8 #include <cmath>
 9 #include <map>
10 #define ll __int64
11 using namespace  std;
12 int dp[500005];
13 int q[500005];
14 int sum[500005];
15 int head,tail,n,m;
16 int getDP(int i,int j)
17 {
18     return dp[j]+m+(sum[i]-sum[j])*(sum[i]-sum[j]);
19 }
20 int getUP(int j,int k)
21 {
22     return dp[j]+sum[j]*sum[j]-(dp[k]+sum[k]*sum[k]);
23 }
24 int getdown(int j,int k)
25 {
26     return 2*(sum[j]-sum[k]);
27 }
28 int main()
29 {
30     while(scanf("%d %d",&n,&m)==2)
31     {
32         for(int i=1; i<=n; i++)
33             scanf("%d",&sum[i]);
34         sum[0]=dp[0]=0;
35         for(int i=1; i<=n; i++)
36             sum[i]+=sum[i-1];
37         head=tail=0;
38         q[tail++]=0;
39         for(int i=1; i<=n; i++)
40         {
41             while(head+1<tail && getUP(q[head+1],q[head])<=sum[i]*getdown(q[head+1],q[head]))
42                 head++;
43             dp[i]=getDP(i,q[head]);
44             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]))
45                 tail--;
46             q[tail++]=i;
47         }
48         printf("%d\n",dp[n]);
49     }
50     return 0;
51 }