#include<bits/stdc++.h>
using namespace std;
using ll=long long;
int n,q;
ll w[100100],psum[100100];
int s[100100],t[100100],fa[100100];
ll f[100100],g[100100];
inline int anc(int x)
{
	while(fa[x]!=x) x=fa[x]=fa[fa[x]];
	return x;
}
mt19937_64 rnd(20210448);
void _sort(vector<int> vec,vector<int> &sorted)
{
	if(!vec.size()) return ;
	int ind=rnd()%vec.size();
	int x=vec[ind];
	int a=min(s[x],t[x]),b=max(s[x],t[x]);
	vector<int> v1,v2;
	for(auto y:vec)
		if(y!=x)
		{
			if(a<=s[y]&&s[y]<=b&&a<=t[y]&&t[y]<=b)
				v1.push_back(y);
			else
				v2.push_back(y);
		}
	sort(v1.begin(),v1.end(),[&](int u,int v)
	{
		if(s[x]<t[x])
			return pair<int,int>(s[u]-s[x],t[x]-t[u])>pair<int,int>(s[v]-s[x],t[x]-t[v]);
		return pair<int,int>(t[u]-t[x],s[x]-s[u])>pair<int,int>(t[v]-t[x],s[x]-s[v]);
	});
	for(auto x:v1)
		sorted.push_back(x);
	sorted.push_back(x);
	sort(v2.begin(),v2.end(),[&](int u,int v)
	{
		if(s[x]<t[x])
			return pair<int,int>((s[x]-s[u]+n)%n,(t[u]-t[x]+n)%n)<pair<int,int>((s[x]-s[v]+n)%n,(t[v]-t[x]+n)%n);
		return pair<int,int>((t[x]-t[u]+n)%n,(s[u]-s[x]+n)%n)<pair<int,int>((t[x]-t[v]+n)%n,(s[v]-s[x]+n)%n);
	});
	for(auto x:v2)
		sorted.push_back(x);
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>q;
	for(int i=1;i<=n;i++)
	{
		cin>>w[i];
		psum[i]=psum[i-1]+w[i];
	}
	for(int i=1;i<=q;i++)
		fa[i]=i;
	for(int i=1;i<=q;i++)
		cin>>s[i]>>t[i];
	for(int i=1;i<=q;i++)
		for(int j=i+1;j<=q;j++) if(j<=i+500)
		{
			int a=min(s[i],t[i]),b=max(s[i],t[i]);
			if(((s[j]>a&&s[j]<b)^(t[j]>a&&t[j]<b))&&s[j]!=s[i]&&s[j]!=t[i]&&t[j]!=s[i]&&t[j]!=t[i])
				fa[anc(i)]=anc(j);
			else if((a>=max(s[j],t[j])||b<=min(s[j],t[j]))^(s[j]<t[j])^(s[i]<t[i]))
				fa[anc(i)]=anc(j);
		}
	vector<int> vec,sorted;
	for(int i=1;i<=q;i++)
		if(fa[i]==i)
			vec.push_back(i);
	_sort(vec,sorted);
	for(int i=1;i<=q;i++)
		if(s[i]<t[i])
		{
			f[anc(i)]+=psum[t[i]]-psum[s[i]];
			g[anc(i)]+=psum[n]-psum[t[i]]+psum[s[i]];
		}
		else
		{
			f[anc(i)]+=psum[n]-psum[s[i]]+psum[t[i]];
			g[anc(i)]+=psum[s[i]]-psum[t[i]];
		}
	if(s[sorted[0]]<t[sorted[0]])
	{
		ll tot=0;
		ll ans=0x3f3f3f3f3f3f3f3f;
		for(auto x:sorted)
			tot+=g[x];
		ans=tot;
		for(auto x:sorted)
		{
			tot+=f[x]-g[x];
			ans=min(ans,tot);
		}
		cout<<ans<<endl;
	}
	else
	{
		ll tot=0;
		ll ans=0x3f3f3f3f3f3f3f3f;
		for(auto x:sorted)
			tot+=f[x];
		ans=tot;
		for(auto x:sorted)
		{
			tot+=g[x]-f[x];
			ans=min(ans,tot);
		}
		cout<<ans<<endl;
	}
	return 0;
}