I I U C O N L I N E C O N T E S T 2 0 0 8 |
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Problem B: Triples |
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Input: standard input |
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Given a sequence of positive integers. You need to find the number of triples in that sequence. For this problem, (x, y, z) constructs a triple if and only if x + y = z. So, (1, 2, 3) is a triple, where (3, 4, 5) is not.
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Input |
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Each input set starts with a positive integer N. Next few lines contain N positive integers. Input is terminated by EOF.
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Output |
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For each case, print the number of triples in a line.
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Constraints |
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- 3 ≤ N ≤ 5000
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Sample Input |
Output for Sample Input |
6 1 2 3 4 5 6 6 1 2 4 8 16 32 3 100000000 200000000 100000000 5 1 1 1 2 2 |
6 0 1 6 |
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Problem setter: Md. Kamruzzaman |