addRange method

void addRange(
  1. int l,
  2. int r,
  3. int delta
)

Adds delta to the logical range l..r (inclusive) in O(1). Audited: 2026-06-12 11:26 EDT

Implementation

void addRange(int l, int r, int delta) {
  // Reject out-of-range AND reversed ranges (l > r). Without the l > r guard a
  // reversed range writes a positive delta at l and a negative at r+1 < l,
  // silently corrupting the recovered array instead of being a clean no-op.
  if (l < 0 || r >= _d.length - 1 || l > r) return;
  _d[l] += delta;
  _d[r + 1] -= delta;
}