mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
21 lines
494 B
Solidity
21 lines
494 B
Solidity
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contract collatz {
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function run(uint x) public returns(uint y) {
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while ((y = x) > 1) {
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if (x % 2 == 0) x = evenStep(x);
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else x = oddStep(x);
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}
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}
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function evenStep(uint x) public returns(uint y) {
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return x / 2;
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}
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function oddStep(uint x) public returns(uint y) {
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return 3 * x + 1;
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}
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}
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// ----
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// run(uint256): 0 -> 0
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// run(uint256): 1 -> 1
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// run(uint256): 2 -> 1
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// run(uint256): 8 -> 1
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// run(uint256): 127 -> 1
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