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You are given an array A1,A2...AN. You have to tell how many pairs (i, j) exist such that 1 ≤ i < j ≤ N and Ai XOR Aj is odd.
Input and Output First line T, the number of testcases. Each testcase: first line N, followed by N integers in next line. For each testcase, print the required answer in one line. Constraints 1 ≤ T ≤ 10 1 ≤ N ≤ 105 0 ≤ Ai ≤ 109
2 Réponses
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examples....
SAMPLE INPUT
2
3
1 2 3
4
1 2 3 4
SAMPLE OUTPUT
2 4
Explanation
For first testcase: 1 XOR 2 is 3 and 2 XOR 3 is 1. So, 2 valid pairs. For second testcase: 1 XOR 2 is 3 and 2 XOR 3 is 1 and 1 XOR 4 is 5 and 3 XOR 4 is 7. So, 4 valid pairs.
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Can you give an example please? I'm not sure if I understood well.