According to problem rules:

Is it right that for all 1 <= i <= j <= S the following inequality
holds:
Ai + Ai-1 + ... + Aj <= (j &#8211; i + 1) + N?

I do not understand the last line.
if j>=i then why Ai + Ai-1 + ... + Aj

Does it mean
Ai+Ai-1+Ai-2+...+A1+Aj or Aj+Aj-1+Aj-2+Aj-3+...+Ai+1+Ai

if yes then waht should i do when i=j
Ai+Aj or olny Ai

It should be Ai + Ai+1 + ... + Aj.

> It should be Ai + Ai+1 + ... + Aj.

Right. It is missprint here.