#include<bits/stdc++.h>
using namespace std;
int a[1000001],b[1000001]; 
int main(){
	//freopen("que.in","r",stdin);
	//freopen("que.out","w",stdout);
	int n,m;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	for(int i=1;i<=m;i++){
		int L,R,C;
		cin>>L>>R>>C;
		b[L]+=C;
		b[R+1]-=C;
	}
	for(int i=1;i<=n;i++){
		b[i]=b[i]+b[i-1];
		a[i]+=b[i];
	}
	int minn=1000001;
	for(int i=1;i<=n;i++){
		if(a[i]<minn){
			minn=a[i];
		}
	}
	cout<<minn;
	return 0;
}