Lessons from Range Sum

Three lessons from this problem:

$1.$ Block size matters: use $B = \lfloor\sqrt{n}\rfloor$ or slightly larger to avoid edge cases

$2.$ Handle same-block queries separately: when $l$ and $r$ are in the same block, iterate directly

$3.$ The constant factor is higher than segment trees, but implementation is simpler Sqrt decomposition shines when you need a quick, correct solution. But can you use it for minimum queries too?