Number of Sub-arrays With Odd Sum LeetCode solution in Java

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// odd-even=odd
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// even-odd=odd
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class Solution {
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  public int numOfSubarrays(int[] arr) {
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    long ans = 0;
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    int even = 0;
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    int odd = 0;
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    long sum = 0;
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    for (int i = 0; i < arr.length; i++) {
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      sum += arr[i];
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      if (sum % 2 == 0) {
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        ans += odd;
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        even++;
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      } else {
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        ans += even + 1;
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        odd++;
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      }
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    }
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    return (int) (ans % (1000000007));
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  }
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}