20 lines
627 B
Plaintext
20 lines
627 B
Plaintext
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import "../../casts/u32_to_bits";
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import "../bool/pack256";
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// pack 256 big-endian bits into one field element
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// Note: This is not a injective operation as `p` is smaller than `2**256 - 1 for bn128
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// For example, `[0, 0,..., 0]` and `bits(p)` both point to `0`
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def main(u32[8] input) -> field {
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bool[256] bits = [
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...u32_to_bits(input[0]),
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...u32_to_bits(input[1]),
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...u32_to_bits(input[2]),
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...u32_to_bits(input[3]),
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...u32_to_bits(input[4]),
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...u32_to_bits(input[5]),
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...u32_to_bits(input[6]),
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...u32_to_bits(input[7])
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];
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return pack256(bits);
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}
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