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Improvement thanks to Ziggit advice

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This commit is contained in:
Jack Jackson 2025-01-20 08:58:46 -08:00
parent 70a4c8615f
commit 0949fc75fd
1 changed files with 3 additions and 13 deletions
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16
solutions/17.zig
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@ -316,23 +316,13 @@ fn find_quine_value_of_a(p: []const u4, allocator: std.mem.Allocator) void {
}
var next_cand_it = next_candidates.keyIterator();
while (next_cand_it.next()) |k| {
// Memory management is fucking insane.
// If I'd instead just done:
// ```
// _ = next_candidates.remove(k.*)
// candidates.put(k.*) catch unreachable;
// ```
// Then - presumably because `k` is a pointer rather than the actual value - the value put into candidates will be some entirely different value than the one retrieved from `next_candidates`
const actual_value = k.*;
print("DEBUG - found {} in next_candidates (to be removed)\n", .{actual_value});
_ = next_candidates.remove(actual_value);
print("DEBUG - transferring {} from next_candidates to candidates for the next iteration\n", .{actual_value});
candidates.put(actual_value, true) catch unreachable;
// Thanks to https://ziggit.dev/t/how-to-idiomatically-move-values-from-one-set-to-another-and-how-should-i-think-about-keyiterator-values-under-the-hood/8007/4?u=scubbo
candidates.put(next_candidates.fetchRemove(k).?.key, true) catch unreachable;
}
}
print("Finished processing - all candidates are: ", .{});
var lowest: u64 = 9999999999999999999;
var lowest: u64 = 9999999999999999999; // `std.math.inf` leads to errors because of unreachable code
var cand_it = candidates.keyIterator();
while (cand_it.next()) |c| {
print("{}, ", .{c.*});