Almost Increasing Sequence

https://app.codesignal.com/arcade/intro/level-2/2mxbGwLzvkTCKAJMG/solutions

Given a sequence of integers as an array, determine whether it is possible to obtain a strictly increasing sequence by removing no more than one element from the array.

Note: sequence a0, a1, ..., an is considered to be a strictly increasing if a0 < a1 < ... < an. Sequence containing only one element is also considered to be strictly increasing.

Example

• For sequence = [1, 3, 2, 1], the output should be
  almostIncreasingSequence(sequence) = false.

  There is no one element in this array that can be removed in order to get a strictly increasing sequence.

• For sequence = [1, 3, 2], the output should be
  almostIncreasingSequence(sequence) = true.

  You can remove 3 from the array to get the strictly increasing sequence [1, 2]. Alternately, you can remove 2 to get the strictly increasing sequence [1, 3].

Input/Output

• [execution time limit] 3 seconds (java)

• [input] array.integer sequence

  Guaranteed constraints:
  2 ≤ sequence.length ≤ 105,
  -105 ≤ sequence[i] ≤ 105.

• [output] boolean

  • Return true if it is possible to remove one element from the array in order to get a strictly increasing sequence, otherwise return false.

---

	boolean almostIncreasingSequence(int[] sequence) {
	int mismatched = 0;
	for (int i = 0; i < sequence.length - 1; i++) {
	if (sequence[i + 1] <= sequence[i]) {
	mismatched++;
	boolean neighbor = (i > 0 && sequence[i + 1] <= sequence[i - 1]);
	boolean skip = (i + 2 < sequence.length && sequence[i + 2] <= sequence[i]);
	if (neighbor && skip || mismatched > 1) {
	return false;
	}
	}
	}
	return true;
	}

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