C++ :

#include<bits/stdc++.h>
using namespace std;
long long a[1000005],n,x,y,zj,fs,cf[1000005],p,ans,df;
int main(){
    cin>>n>>p;
    for(int i=1;i<=n;++i)
    {
    	scanf("%lld",&a[i]);
    	cf[i]=a[i]-a[i-1];
    }
    while(p--)
    {
    	scanf("%lld %lld %lld",&x,&y,&zj);
    	cf[x]+=zj;
    	cf[y+1]-=zj;
    }
    ans=cf[1];
    for(int i=1;i<=n;++i)
    {
    	df=df+cf[i];
    	ans=min(ans,df);
    	//cout<<cf[i]<<" ";
    }
    cout<<ans;
    return 0;
}