include[HTML_REMOVED]
using namespace std;
const int N=1e5+10;
int a[N],s[N];
int main()
{
int n,m; cin>>n>>m;
s[0]=a[0]=0;
for(int i=1;i<=n;i++) cin>>a[i];
for(int i=1;i<=n;i++) s[i]=s[i-1]+a[i];
while(m--)
{
int l,r; cin>>l>>r;
cout<<s[r]-s[l-1]<<endl;
}
return 0;
}