#include<bits/stdc++.h>

using namespace std;
namespace IO {
constexpr int MAXSIZE = 1 << 20;
char buf[MAXSIZE], *p1, *p2;
#define gc()                                                               \
  (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, MAXSIZE, stdin), p1 == p2) \
       ? EOF                                                               \
       : *p1++)

int rd() {
  int x = 0, f = 1;
  char c = gc();
  while (!isdigit(c)) {
    if (c == '-') f = -1;
    c = gc();
  }
  while (isdigit(c)) x = x * 10 + (c ^ 48), c = gc();
  return x * f;
}

char pbuf[1 << 20], *pp = pbuf;

void push(const char &c) {
  if (pp - pbuf == 1 << 20) fwrite(pbuf, 1, 1 << 20, stdout), pp = pbuf;
  *pp++ = c;
}

}  // namespace IO
inline int read(){
    int x = 0, t = 1;
    char ch=getchar(); 
    while(ch<'0'||ch>'9'){
        if(ch=='-')
            t=-1;
        ch=getchar();
    }
    while(ch>='0'&&ch<='9'){
        x=(x<<1)+(x<<3)+(ch^48);  
        ch=getchar();
    }
    return x*t;
}
inline void write(__int128 x)
{
    if(x<0){
    	putchar('-');
		x=-x;
	}
    if(x>9) 
		write(x/10);
    putchar(x%10+'0');
}
const int N=2e6;
int n,m;
__int128 ans=0,lans;
int a[N+5],id[N+5],id2[N+5];
int fa[N+5],fr[N+5],lim[N+5];
long long sum[N+5];
int cs=0;
int Find(int u){//cs++;
	// return u;
	return (u!=fa[u]?fa[u]=Find(fa[u]):u);
}
void Solve(int l,int r){
	if(l==r){
		id[l]=l;
		lans+=1ll*(m-a[l]+1)*a[l];
		return;
	}
	int mid=l+r>>1;
	Solve(l,mid);Solve(mid+1,r);
	int l1=l,l2=mid+1,l3=l;
	while(l1<=mid||l2<=r){
		if((l2>r)||(l1<=mid&&a[id[l1]]<=a[id[l2]]))id2[l3++]=id[l1],l1++;
		else id2[l3++]=id[l2],l2++;
	}
	for(int i=l;i<=r;i++)id[i]=id2[i];
	for(int i=l;i<=r;i++)fa[i]=i,sum[i]=0,fr[i]=0;
	stack<int>L,R;
	ans=0;
	for(int j=l;j<=r;j++){
		int x=id[j];
		if(x<=mid){
			while(!L.empty()&&L.top()<x){
				int y=L.top();L.pop();
				sum[x]+=sum[y];
				ans-=(__int128)sum[y]*(x-y);
				if(fr[y]==0)ans-=(__int128)a[y]*lim[y]*(r-mid);
				else {
					int z=Find(fr[y]);
					sum[z]-=1ll*a[y]*lim[y];
					ans-=(__int128)a[y]*lim[y]*(z-mid-1);
				}
				fa[y]=x;fr[y]=-1;
			}
			for(int i=j-1;i>=l;i--){
				if(id[i]<=mid)break;
				int y=id[i];
				if(fr[y]==-1)continue;
				fr[y]=x;sum[x]+=1ll*lim[y]*a[y];
				ans-=(__int128)a[y]*lim[y]*(x-l+1);
			}
			if(!L.empty()){
				int y=L.top();
				if(fr[y]==0)ans+=(__int128)a[y]*(r-mid)*(y-x-lim[y]);
				else {
					int z=Find(fr[y]);
					sum[z]+=1ll*a[y]*(y-x-lim[y]);
					ans+=(__int128)a[y]*(z-mid-1)*(y-x-lim[y]);
				}
				lim[y]=y-x;
			}
			lim[x]=x-l+1;L.push(x);
			ans+=(__int128)a[x]*lim[x]*(r-mid);
		}
		else {
			while(!R.empty()&&R.top()>x){
				int y=R.top();R.pop();
				sum[x]+=sum[y];
				ans-=(__int128)sum[y]*(y-x);
				if(fr[y]==0)ans-=(__int128)a[y]*lim[y]*(mid-l+1);
				else {
					int z=Find(fr[y]);
					sum[z]-=1ll*a[y]*lim[y];
					ans-=(__int128)a[y]*lim[y]*(mid-z);
				}
				fa[y]=x;fr[y]=-1;
			}
			for(int i=j-1;i>=l;i--){
				if(id[i]>mid)break;
				int y=id[i];
				if(fr[y]==-1)continue;
				fr[y]=x;sum[x]+=1ll*lim[y]*a[y];
				ans-=(__int128)a[y]*lim[y]*(r-x+1);
			}
			if(!R.empty()){
				int y=R.top();
				if(fr[y]==0)ans+=(__int128)a[y]*(mid-l+1)*(x-y-lim[y]);
				else {
					int z=Find(fr[y]);
					sum[z]+=1ll*a[y]*(x-y-lim[y]);
					ans+=(__int128)a[y]*(mid-z)*(x-y-lim[y]);
				}
				lim[y]=x-y;
			}
			lim[x]=r-x+1;R.push(x);
			ans+=(__int128)a[x]*lim[x]*(mid-l+1);
		}
		lans+=ans*(j<r?a[id[j+1]]-a[x]:m-a[x]+1);
	}
}
int main(){
	n=IO::rd();m=IO::rd();
	for(int i=1;i<=n;i++)a[i]=IO::rd();
	Solve(1,n);
	write(lans);
	return 0;
}