text: If the input index is in range of this node , then update the value of the node and its children
code: st [ si ] = st [ si ] + diff NEW_LINE if se != ss : NEW_LINE INDENT mid = getMid ( ss , se ) NEW_LINE updateValueUtil ( st , ss , mid , i , diff , 2 * si + 1 ) NEW_LINE updateValueUtil ( st , mid + 1 , se , i , diff , 2 * si + 2 ) NEW_LINE DEDENT