include[HTML_REMOVED]
using namespace std;
const int N=100006;
int arr[N],s[N];
int main()
{
int n,m,l,r;
cin>>n>>m;
for(int i=1;i<=n;i++)
{
cin>>arr[i];
s[i]=s[i-1]+arr[i];
}
while(m–)
{
cin>>l>>r;
cout<<s[r]-s[l-1]<<endl;
}
}