Is Sum Of Consecutive 2

Description

Find the number of ways to express n as sum of some (at least two) consecutive positive integers.

Example

For n = 9, the output should be isSumOfConsecutive2(n) = 2.

There are two ways to represent n = 9: 2 + 3 + 4 = 9 and 4 + 5 = 9.
For n = 8, the output should be isSumOfConsecutive2(n) = 0.

There are no ways to represent n = 8.

Input/Output

[execution time limit] 4 seconds (js)
[input] integer n

A positive integer.

Guaranteed constraints:
1 ≤ n ≤ 10⁴.
[output] integer

[JavaScript (ES6)] Syntax Tips

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Solution

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function isSumOfConsecutive2(n) {
  var r = 0;
  for (var i = 2; i < n / 2; i++) {
    if (i % 2) {
      if (Math.round(n / i) * i == n && n / i > i / 2)
        r++;
    } else {
      if (Math.floor(n / i) * i != n && (Math.floor(n / i) + Math.ceil(n / i)) == n * 2 / i && n / i > i / 2)
        r++;
    }
  }
  return r;
}